diff --git a/evidence/verify_test.go b/evidence/verify_test.go
index 880088b5c..dbccb1ced 100644
--- a/evidence/verify_test.go
+++ b/evidence/verify_test.go
@@ -193,6 +193,7 @@ func TestVerifyLightClientAttack_Equivocation(t *testing.T) {
 	conflictingVals, conflictingPrivVals := factory.RandValidatorSet(5, 10)
 
 	conflictingHeader, err := factory.MakeHeader(&types.Header{
+		ChainID:        evidenceChainID,
 		Height:         10,
 		Time:           defaultEvidenceTime,
 		ValidatorsHash: conflictingVals.Hash(),
@@ -200,6 +201,7 @@ func TestVerifyLightClientAttack_Equivocation(t *testing.T) {
 	require.NoError(t, err)
 
 	trustedHeader, _ := factory.MakeHeader(&types.Header{
+		ChainID:            evidenceChainID,
 		Height:             10,
 		Time:               defaultEvidenceTime,
 		ValidatorsHash:     conflictingHeader.ValidatorsHash,
@@ -286,6 +288,7 @@ func TestVerifyLightClientAttack_Amnesia(t *testing.T) {
 	conflictingVals, conflictingPrivVals := factory.RandValidatorSet(5, 10)
 
 	conflictingHeader, err := factory.MakeHeader(&types.Header{
+		ChainID:        evidenceChainID,
 		Height:         height,
 		Time:           defaultEvidenceTime,
 		ValidatorsHash: conflictingVals.Hash(),
@@ -293,6 +296,7 @@ func TestVerifyLightClientAttack_Amnesia(t *testing.T) {
 	require.NoError(t, err)
 
 	trustedHeader, _ := factory.MakeHeader(&types.Header{
+		ChainID:            evidenceChainID,
 		Height:             height,
 		Time:               defaultEvidenceTime,
 		ValidatorsHash:     conflictingHeader.ValidatorsHash,
@@ -485,16 +489,26 @@ func makeLunaticEvidence(
 
 	conflictingPrivVals = orderPrivValsByValSet(t, conflictingVals, conflictingPrivVals)
 
-	commonHeader := factory.MakeRandomHeader()
-	commonHeader.Height = commonHeight
-	commonHeader.Time = commonTime
-	trustedHeader := factory.MakeRandomHeader()
-	trustedHeader.Height = height
+	commonHeader, err := factory.MakeHeader(&types.Header{
+		ChainID: evidenceChainID,
+		Height:  commonHeight,
+		Time:    commonTime,
+	})
+	require.NoError(t, err)
+	trustedHeader, err := factory.MakeHeader(&types.Header{
+		ChainID: evidenceChainID,
+		Height:  height,
+		Time:    defaultEvidenceTime,
+	})
+	require.NoError(t, err)
 
-	conflictingHeader := factory.MakeRandomHeader()
-	conflictingHeader.Height = height
-	conflictingHeader.Time = attackTime
-	conflictingHeader.ValidatorsHash = conflictingVals.Hash()
+	conflictingHeader, err := factory.MakeHeader(&types.Header{
+		ChainID:        evidenceChainID,
+		Height:         height,
+		Time:           attackTime,
+		ValidatorsHash: conflictingVals.Hash(),
+	})
+	require.NoError(t, err)
 
 	blockID := factory.MakeBlockIDWithHash(conflictingHeader.Hash())
 	voteSet := types.NewVoteSet(evidenceChainID, height, 1, tmproto.SignedMsgType(2), conflictingVals)
diff --git a/types/validation.go b/types/validation.go
index b3b448004..ce91711a6 100644
--- a/types/validation.go
+++ b/types/validation.go
@@ -1,30 +1,141 @@
 package types
 
 import (
+	"errors"
 	"fmt"
-	"time"
 
+	"github.com/tendermint/tendermint/crypto/batch"
 	"github.com/tendermint/tendermint/crypto/tmhash"
-	tmtime "github.com/tendermint/tendermint/types/time"
+	tmmath "github.com/tendermint/tendermint/libs/math"
 )
 
-// ValidateTime does a basic time validation ensuring time does not drift too
-// much: +/- one year.
-// TODO: reduce this to eg 1 day
-// NOTE: DO NOT USE in ValidateBasic methods in this package. This function
-// can only be used for real time validation, like on proposals and votes
-// in the consensus. If consensus is stuck, and rounds increase for more than a day,
-// having only a 1-day band here could break things...
-// Can't use for validating blocks because we may be syncing years worth of history.
-func ValidateTime(t time.Time) error {
-	var (
-		now     = tmtime.Now()
-		oneYear = 8766 * time.Hour
-	)
-	if t.Before(now.Add(-oneYear)) || t.After(now.Add(oneYear)) {
-		return fmt.Errorf("time drifted too much. Expected: -1 < %v < 1 year", now)
+// VerifyCommit verifies +2/3 of the set had signed the given commit.
+//
+// It checks all the signatures! While it's safe to exit as soon as we have
+// 2/3+ signatures, doing so would impact incentivization logic in the ABCI
+// application that depends on the LastCommitInfo sent in BeginBlock, which
+// includes which validators signed. For instance, Gaia incentivizes proposers
+// with a bonus for including more than +2/3 of the signatures.
+func VerifyCommit(chainID string, vals *ValidatorSet, blockID BlockID,
+	height int64, commit *Commit) error {
+
+	// run a basic validation of the arguments
+	if err := verifyBasicValsAndCommit(vals, commit, height, blockID); err != nil {
+		return err
 	}
-	return nil
+
+	// calculate voting power needed. Note that total voting power is capped to
+	// 1/8th of max int64 so this operation should never overflow
+	votingPowerNeeded := vals.TotalVotingPower() * 2 / 3
+
+	// ignore all absent signatures
+	ignore := func(c CommitSig) bool { return c.Absent() }
+
+	// only count the signatures that are for the block
+	count := func(c CommitSig) bool { return c.ForBlock() }
+
+	// attempt to batch verify
+	cacheSignBytes, success, err := tryVerifyCommitBatch(
+		chainID, vals, commit, votingPowerNeeded, ignore, count, true, true)
+	if err != nil {
+		return err
+	}
+	if success {
+		return nil
+	}
+
+	// if verification failed or is not supported then fallback to single verification
+	return verifyCommitSingle(chainID, vals, commit, votingPowerNeeded,
+		cacheSignBytes, ignore, count, true, true)
+}
+
+// LIGHT CLIENT VERIFICATION METHODS
+
+// VerifyCommitLight verifies +2/3 of the set had signed the given commit.
+//
+// This method is primarily used by the light client and does not check all the
+// signatures.
+func VerifyCommitLight(chainID string, vals *ValidatorSet, blockID BlockID,
+	height int64, commit *Commit) error {
+
+	// run a basic validation of the arguments
+	if err := verifyBasicValsAndCommit(vals, commit, height, blockID); err != nil {
+		return err
+	}
+
+	// calculate voting power needed
+	votingPowerNeeded := vals.TotalVotingPower() * 2 / 3
+
+	// ignore all commit signatures that are not for the block
+	ignore := func(c CommitSig) bool { return !c.ForBlock() }
+
+	// count all the remaining signatures
+	count := func(c CommitSig) bool { return true }
+
+	// attempt to batch verify
+	cacheSignBytes, success, err := tryVerifyCommitBatch(
+		chainID, vals, commit, votingPowerNeeded, ignore, count, false, true)
+	if err != nil {
+		return err
+	}
+	if success {
+		return nil
+	}
+
+	// if verification failed or is not supported then fallback to single verification
+	return verifyCommitSingle(chainID, vals, commit, votingPowerNeeded,
+		cacheSignBytes, ignore, count, false, true)
+
+}
+
+// VerifyCommitLightTrusting verifies that trustLevel of the validator set signed
+// this commit.
+//
+// NOTE the given validators do not necessarily correspond to the validator set
+// for this commit, but there may be some intersection.
+//
+// This method is primarily used by the light client and does not check all the
+// signatures.
+func VerifyCommitLightTrusting(chainID string, vals *ValidatorSet, commit *Commit, trustLevel tmmath.Fraction) error {
+	// sanity checks
+	if vals == nil {
+		return errors.New("nil validator set")
+	}
+	if trustLevel.Denominator == 0 {
+		return errors.New("trustLevel has zero Denominator")
+	}
+	if commit == nil {
+		return errors.New("nil commit")
+	}
+
+	// safely calculate voting power needed.
+	totalVotingPowerMulByNumerator, overflow := safeMul(vals.TotalVotingPower(), int64(trustLevel.Numerator))
+	if overflow {
+		return errors.New("int64 overflow while calculating voting power needed. please provide smaller trustLevel numerator")
+	}
+	votingPowerNeeded := totalVotingPowerMulByNumerator / int64(trustLevel.Denominator)
+
+	// ignore all commit signatures that are not for the block
+	ignore := func(c CommitSig) bool { return !c.ForBlock() }
+
+	// count all the remaining signatures
+	count := func(c CommitSig) bool { return true }
+
+	// attempt to batch verify commit. As the validator set doesn't necessarily
+	// correspond with the validator set that signed the block we need to look
+	// up by address rather than index.
+	cacheSignBytes, success, err := tryVerifyCommitBatch(
+		chainID, vals, commit, votingPowerNeeded, ignore, count, false, false)
+	if err != nil {
+		return err
+	}
+	if success {
+		return nil
+	}
+
+	// attempt with single verification
+	return verifyCommitSingle(chainID, vals, commit, votingPowerNeeded,
+		cacheSignBytes, ignore, count, false, false)
 }
 
 // ValidateHash returns an error if the hash is not empty, but its
@@ -38,3 +149,211 @@ func ValidateHash(h []byte) error {
 	}
 	return nil
 }
+
+// Batch verification
+
+// tryVerifyCommitBatch attempts to batch verify. If it is not supported or
+// verification fails it returns false. If there is an error in the signatures
+// or the way that they are counted an error is returned. A cache of all the
+// commits in byte form is returned in case it needs to be used again for single
+// verification
+func tryVerifyCommitBatch(
+	chainID string,
+	vals *ValidatorSet,
+	commit *Commit,
+	votingPowerNeeded int64,
+	ignoreSig func(CommitSig) bool,
+	countSig func(CommitSig) bool,
+	countAllSignatures bool,
+	lookUpByIndex bool,
+) (map[string][]byte, bool, error) {
+	var (
+		val                *Validator
+		valIdx             int32
+		seenVals                 = make(map[int32]int, len(commit.Signatures))
+		talliedVotingPower int64 = 0
+		// we keep a cache of the signed bytes to make it quicker to verify
+		// individually if we need to
+		cacheSignBytes = make(map[string][]byte, len(commit.Signatures))
+	)
+	// attempt to create a batch verifier
+	bv, ok := batch.CreateBatchVerifier(vals.GetProposer().PubKey)
+	// check if batch verification is supported
+	if !ok || len(commit.Signatures) < 2 {
+		return cacheSignBytes, false, nil
+	}
+
+	for idx, commitSig := range commit.Signatures {
+		// skip over signatures that should be ignored
+		if ignoreSig(commitSig) {
+			continue
+		}
+
+		// If the vals and commit have a 1-to-1 correspondance we can retrieve
+		// them by index else we need to retrieve them by address
+		if lookUpByIndex {
+			val = vals.Validators[idx]
+		} else {
+			valIdx, val = vals.GetByAddress(commitSig.ValidatorAddress)
+
+			// if the signature doesn't belong to anyone in the validator set
+			// then we just skip over it
+			if val == nil {
+				continue
+			}
+
+			// because we are getting validators by address we need to make sure
+			// that the same validator doesn't commit twice
+			if firstIndex, ok := seenVals[valIdx]; ok {
+				secondIndex := idx
+				return cacheSignBytes, false, fmt.Errorf("double vote from %v (%d and %d)", val, firstIndex, secondIndex)
+			}
+			seenVals[valIdx] = idx
+		}
+
+		// Validate signature.
+		voteSignBytes := commit.VoteSignBytes(chainID, int32(idx))
+		// cache the signBytes in case batch verification fails
+		cacheSignBytes[string(val.PubKey.Bytes())] = voteSignBytes
+
+		// add the key, sig and message to the verifier
+		if err := bv.Add(val.PubKey, voteSignBytes, commitSig.Signature); err != nil {
+			return cacheSignBytes, false, err
+		}
+
+		// If this signature counts then add the voting power of the validator
+		// to the tally
+		if countSig(commitSig) {
+			talliedVotingPower += val.VotingPower
+		}
+
+		// if we don't need to verify all signatures and already have sufficient
+		// voting power we can break from batching and verify all the signatures
+		if !countAllSignatures && talliedVotingPower > votingPowerNeeded {
+			break
+		}
+	}
+
+	// ensure that we have batched together enough signatures to exceed the
+	// voting power needed else there is no need to even verify
+	if got, needed := talliedVotingPower, votingPowerNeeded; got <= needed {
+		return cacheSignBytes, false, ErrNotEnoughVotingPowerSigned{Got: got, Needed: needed}
+	}
+
+	// attempt to verify the batch. If this fails, fall back to single
+	// verification
+	if bv.Verify() {
+		// success
+		return cacheSignBytes, true, nil
+	}
+
+	// verification failed
+	return cacheSignBytes, false, nil
+}
+
+// Single Verification
+
+// verifyCommitSingle single verifies commits.
+// If a key does not support batch verification, or batch verification fails this will be used
+// This method is used to check all the signatures included in a commit.
+// It is used in consensus for validating a block LastCommit.
+// CONTRACT: both commit and validator set should have passed validate basic
+func verifyCommitSingle(
+	chainID string,
+	vals *ValidatorSet,
+	commit *Commit,
+	votingPowerNeeded int64,
+	cachedVals map[string][]byte,
+	ignoreSig func(CommitSig) bool,
+	countSig func(CommitSig) bool,
+	countAllSignatures bool,
+	lookUpByIndex bool,
+) error {
+	var (
+		val                *Validator
+		valIdx             int32
+		seenVals                 = make(map[int32]int, len(commit.Signatures))
+		talliedVotingPower int64 = 0
+		voteSignBytes      []byte
+	)
+	for idx, commitSig := range commit.Signatures {
+		if ignoreSig(commitSig) {
+			continue
+		}
+
+		// If the vals and commit have a 1-to-1 correspondance we can retrieve
+		// them by index else we need to retrieve them by address
+		if lookUpByIndex {
+			val = vals.Validators[idx]
+		} else {
+			valIdx, val = vals.GetByAddress(commitSig.ValidatorAddress)
+
+			// if the signature doesn't belong to anyone in the validator set
+			// then we just skip over it
+			if val == nil {
+				continue
+			}
+
+			// because we are getting validators by address we need to make sure
+			// that the same validator doesn't commit twice
+			if firstIndex, ok := seenVals[valIdx]; ok {
+				secondIndex := idx
+				return fmt.Errorf("double vote from %v (%d and %d)", val, firstIndex, secondIndex)
+			}
+			seenVals[valIdx] = idx
+		}
+
+		// Check if we have the validator in the cache
+		if cachedVote, ok := cachedVals[string(val.PubKey.Bytes())]; !ok {
+			voteSignBytes = commit.VoteSignBytes(chainID, int32(idx))
+		} else {
+			voteSignBytes = cachedVote
+		}
+
+		if !val.PubKey.VerifySignature(voteSignBytes, commitSig.Signature) {
+			return fmt.Errorf("wrong signature (#%d): %X", idx, commitSig.Signature)
+		}
+
+		// If this signature counts then add the voting power of the validator
+		// to the tally
+		if countSig(commitSig) {
+			talliedVotingPower += val.VotingPower
+		}
+
+		// check if we have enough signatures and can thus exit early
+		if !countAllSignatures && talliedVotingPower > votingPowerNeeded {
+			return nil
+		}
+	}
+
+	if got, needed := talliedVotingPower, votingPowerNeeded; got <= needed {
+		return ErrNotEnoughVotingPowerSigned{Got: got, Needed: needed}
+	}
+
+	return nil
+}
+
+func verifyBasicValsAndCommit(vals *ValidatorSet, commit *Commit, height int64, blockID BlockID) error {
+	if vals == nil {
+		return errors.New("nil validator set")
+	}
+
+	if commit == nil {
+		return errors.New("nil commit")
+	}
+
+	if vals.Size() != len(commit.Signatures) {
+		return NewErrInvalidCommitSignatures(vals.Size(), len(commit.Signatures))
+	}
+
+	// Validate Height and BlockID.
+	if height != commit.Height {
+		return NewErrInvalidCommitHeight(height, commit.Height)
+	}
+	if !blockID.Equals(commit.BlockID) {
+		return fmt.Errorf("invalid commit -- wrong block ID: want %v, got %v",
+			blockID, commit.BlockID)
+	}
+
+	return nil
+}
diff --git a/types/validation_test.go b/types/validation_test.go
new file mode 100644
index 000000000..4fc7b70ff
--- /dev/null
+++ b/types/validation_test.go
@@ -0,0 +1,262 @@
+package types
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	tmmath "github.com/tendermint/tendermint/libs/math"
+	tmproto "github.com/tendermint/tendermint/proto/tendermint/types"
+)
+
+// Check VerifyCommit, VerifyCommitLight and VerifyCommitLightTrusting basic
+// verification.
+func TestValidatorSet_VerifyCommit_All(t *testing.T) {
+	var (
+		round  = int32(0)
+		height = int64(100)
+
+		blockID    = makeBlockID([]byte("blockhash"), 1000, []byte("partshash"))
+		chainID    = "Lalande21185"
+		trustLevel = tmmath.Fraction{Numerator: 2, Denominator: 3}
+	)
+
+	testCases := []struct {
+		description string
+		// vote chainID
+		chainID string
+		// vote blockID
+		blockID BlockID
+		valSize int
+
+		// height of the commit
+		height int64
+
+		// votes
+		blockVotes  int
+		nilVotes    int
+		absentVotes int
+
+		expErr bool
+	}{
+		{"good (batch verification)", chainID, blockID, 3, height, 3, 0, 0, false},
+		{"good (single verification)", chainID, blockID, 1, height, 1, 0, 0, false},
+
+		{"wrong signature (#0)", "EpsilonEridani", blockID, 2, height, 2, 0, 0, true},
+		{"wrong block ID", chainID, makeBlockIDRandom(), 2, height, 2, 0, 0, true},
+		{"wrong height", chainID, blockID, 1, height - 1, 1, 0, 0, true},
+
+		{"wrong set size: 4 vs 3", chainID, blockID, 4, height, 3, 0, 0, true},
+		{"wrong set size: 1 vs 2", chainID, blockID, 1, height, 2, 0, 0, true},
+
+		{"insufficient voting power: got 30, needed more than 66", chainID, blockID, 10, height, 3, 2, 5, true},
+		{"insufficient voting power: got 0, needed more than 6", chainID, blockID, 1, height, 0, 0, 1, true},
+		{"insufficient voting power: got 60, needed more than 60", chainID, blockID, 9, height, 6, 3, 0, true},
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+		t.Run(tc.description, func(t *testing.T) {
+			_, valSet, vals := randVoteSet(tc.height, round, tmproto.PrecommitType, tc.valSize, 10)
+			totalVotes := tc.blockVotes + tc.absentVotes + tc.nilVotes
+			sigs := make([]CommitSig, totalVotes)
+			vi := 0
+			// add absent sigs first
+			for i := 0; i < tc.absentVotes; i++ {
+				sigs[vi] = NewCommitSigAbsent()
+				vi++
+			}
+			for i := 0; i < tc.blockVotes+tc.nilVotes; i++ {
+
+				pubKey, err := vals[vi%len(vals)].GetPubKey(context.Background())
+				require.NoError(t, err)
+				vote := &Vote{
+					ValidatorAddress: pubKey.Address(),
+					ValidatorIndex:   int32(vi),
+					Height:           tc.height,
+					Round:            round,
+					Type:             tmproto.PrecommitType,
+					BlockID:          tc.blockID,
+					Timestamp:        time.Now(),
+				}
+				if i >= tc.blockVotes {
+					vote.BlockID = BlockID{}
+				}
+
+				v := vote.ToProto()
+
+				require.NoError(t, vals[vi%len(vals)].SignVote(context.Background(), tc.chainID, v))
+				vote.Signature = v.Signature
+
+				sigs[vi] = vote.CommitSig()
+
+				vi++
+			}
+			commit := NewCommit(tc.height, round, tc.blockID, sigs)
+
+			err := valSet.VerifyCommit(chainID, blockID, height, commit)
+			if tc.expErr {
+				if assert.Error(t, err, "VerifyCommit") {
+					assert.Contains(t, err.Error(), tc.description, "VerifyCommit")
+				}
+			} else {
+				assert.NoError(t, err, "VerifyCommit")
+			}
+
+			err = valSet.VerifyCommitLight(chainID, blockID, height, commit)
+			if tc.expErr {
+				if assert.Error(t, err, "VerifyCommitLight") {
+					assert.Contains(t, err.Error(), tc.description, "VerifyCommitLight")
+				}
+			} else {
+				assert.NoError(t, err, "VerifyCommitLight")
+			}
+
+			// only a subsection of the tests apply to VerifyCommitLightTrusting
+			if totalVotes != tc.valSize || !tc.blockID.Equals(blockID) || tc.height != height {
+				tc.expErr = false
+			}
+			err = valSet.VerifyCommitLightTrusting(chainID, commit, trustLevel)
+			if tc.expErr {
+				if assert.Error(t, err, "VerifyCommitLightTrusting") {
+					assert.Contains(t, err.Error(), tc.description, "VerifyCommitLightTrusting")
+				}
+			} else {
+				assert.NoError(t, err, "VerifyCommitLightTrusting")
+			}
+		})
+	}
+}
+
+func TestValidatorSet_VerifyCommit_CheckAllSignatures(t *testing.T) {
+	var (
+		chainID = "test_chain_id"
+		h       = int64(3)
+		blockID = makeBlockIDRandom()
+	)
+
+	voteSet, valSet, vals := randVoteSet(h, 0, tmproto.PrecommitType, 4, 10)
+	commit, err := makeCommit(blockID, h, 0, voteSet, vals, time.Now())
+	require.NoError(t, err)
+	require.NoError(t, valSet.VerifyCommit(chainID, blockID, h, commit))
+
+	// malleate 4th signature
+	vote := voteSet.GetByIndex(3)
+	v := vote.ToProto()
+	err = vals[3].SignVote(context.Background(), "CentaurusA", v)
+	require.NoError(t, err)
+	vote.Signature = v.Signature
+	commit.Signatures[3] = vote.CommitSig()
+
+	err = valSet.VerifyCommit(chainID, blockID, h, commit)
+	if assert.Error(t, err) {
+		assert.Contains(t, err.Error(), "wrong signature (#3)")
+	}
+}
+
+func TestValidatorSet_VerifyCommitLight_ReturnsAsSoonAsMajorityOfVotingPowerSigned(t *testing.T) {
+	var (
+		chainID = "test_chain_id"
+		h       = int64(3)
+		blockID = makeBlockIDRandom()
+	)
+
+	voteSet, valSet, vals := randVoteSet(h, 0, tmproto.PrecommitType, 4, 10)
+	commit, err := makeCommit(blockID, h, 0, voteSet, vals, time.Now())
+	require.NoError(t, err)
+	require.NoError(t, valSet.VerifyCommit(chainID, blockID, h, commit))
+
+	// malleate 4th signature (3 signatures are enough for 2/3+)
+	vote := voteSet.GetByIndex(3)
+	v := vote.ToProto()
+	err = vals[3].SignVote(context.Background(), "CentaurusA", v)
+	require.NoError(t, err)
+	vote.Signature = v.Signature
+	commit.Signatures[3] = vote.CommitSig()
+
+	err = valSet.VerifyCommitLight(chainID, blockID, h, commit)
+	assert.NoError(t, err)
+}
+
+func TestValidatorSet_VerifyCommitLightTrusting_ReturnsAsSoonAsTrustLevelOfVotingPowerSigned(t *testing.T) {
+	var (
+		chainID = "test_chain_id"
+		h       = int64(3)
+		blockID = makeBlockIDRandom()
+	)
+
+	voteSet, valSet, vals := randVoteSet(h, 0, tmproto.PrecommitType, 4, 10)
+	commit, err := makeCommit(blockID, h, 0, voteSet, vals, time.Now())
+	require.NoError(t, err)
+	require.NoError(t, valSet.VerifyCommit(chainID, blockID, h, commit))
+
+	// malleate 3rd signature (2 signatures are enough for 1/3+ trust level)
+	vote := voteSet.GetByIndex(2)
+	v := vote.ToProto()
+	err = vals[2].SignVote(context.Background(), "CentaurusA", v)
+	require.NoError(t, err)
+	vote.Signature = v.Signature
+	commit.Signatures[2] = vote.CommitSig()
+
+	err = valSet.VerifyCommitLightTrusting(chainID, commit, tmmath.Fraction{Numerator: 1, Denominator: 3})
+	assert.NoError(t, err)
+}
+
+func TestValidatorSet_VerifyCommitLightTrusting(t *testing.T) {
+	var (
+		blockID                       = makeBlockIDRandom()
+		voteSet, originalValset, vals = randVoteSet(1, 1, tmproto.PrecommitType, 6, 1)
+		commit, err                   = makeCommit(blockID, 1, 1, voteSet, vals, time.Now())
+		newValSet, _                  = randValidatorPrivValSet(2, 1)
+	)
+	require.NoError(t, err)
+
+	testCases := []struct {
+		valSet *ValidatorSet
+		err    bool
+	}{
+		// good
+		0: {
+			valSet: originalValset,
+			err:    false,
+		},
+		// bad - no overlap between validator sets
+		1: {
+			valSet: newValSet,
+			err:    true,
+		},
+		// good - first two are different but the rest of the same -> >1/3
+		2: {
+			valSet: NewValidatorSet(append(newValSet.Validators, originalValset.Validators...)),
+			err:    false,
+		},
+	}
+
+	for _, tc := range testCases {
+		err = tc.valSet.VerifyCommitLightTrusting("test_chain_id", commit,
+			tmmath.Fraction{Numerator: 1, Denominator: 3})
+		if tc.err {
+			assert.Error(t, err)
+		} else {
+			assert.NoError(t, err)
+		}
+	}
+}
+
+func TestValidatorSet_VerifyCommitLightTrustingErrorsOnOverflow(t *testing.T) {
+	var (
+		blockID               = makeBlockIDRandom()
+		voteSet, valSet, vals = randVoteSet(1, 1, tmproto.PrecommitType, 1, MaxTotalVotingPower)
+		commit, err           = makeCommit(blockID, 1, 1, voteSet, vals, time.Now())
+	)
+	require.NoError(t, err)
+
+	err = valSet.VerifyCommitLightTrusting("test_chain_id", commit,
+		tmmath.Fraction{Numerator: 25, Denominator: 55})
+	if assert.Error(t, err) {
+		assert.Contains(t, err.Error(), "int64 overflow")
+	}
+}
diff --git a/types/validator_set.go b/types/validator_set.go
index 5bc63868a..8675dec2a 100644
--- a/types/validator_set.go
+++ b/types/validator_set.go
@@ -9,7 +9,6 @@ import (
 	"sort"
 	"strings"
 
-	"github.com/tendermint/tendermint/crypto/batch"
 	"github.com/tendermint/tendermint/crypto/merkle"
 	tmmath "github.com/tendermint/tendermint/libs/math"
 	tmproto "github.com/tendermint/tendermint/proto/tendermint/types"
@@ -653,253 +652,25 @@ func (vals *ValidatorSet) UpdateWithChangeSet(changes []*Validator) error {
 	return vals.updateWithChangeSet(changes, true)
 }
 
-// VerifyCommit verifies +2/3 of the set had signed the given commit.
-//
-// It checks all the signatures! While it's safe to exit as soon as we have
-// 2/3+ signatures, doing so would impact incentivization logic in the ABCI
-// application that depends on the LastCommitInfo sent in BeginBlock, which
-// includes which validators signed. For instance, Gaia incentivizes proposers
-// with a bonus for including more than +2/3 of the signatures.
+// VerifyCommit verifies +2/3 of the set had signed the given commit and all
+// other signatures are valid
 func (vals *ValidatorSet) VerifyCommit(chainID string, blockID BlockID,
 	height int64, commit *Commit) error {
-	if commit == nil {
-		return errors.New("nil commit")
-	}
-
-	if vals.Size() != len(commit.Signatures) {
-		return NewErrInvalidCommitSignatures(vals.Size(), len(commit.Signatures))
-	}
-
-	// Validate Height and BlockID.
-	if height != commit.Height {
-		return NewErrInvalidCommitHeight(height, commit.Height)
-	}
-	if !blockID.Equals(commit.BlockID) {
-		return fmt.Errorf("invalid commit -- wrong block ID: want %v, got %v",
-			blockID, commit.BlockID)
-	}
-
-	votingPowerNeeded := vals.TotalVotingPower() * 2 / 3
-	var (
-		talliedVotingPower int64 = 0
-		err                error
-		cacheSignBytes     = make(map[string][]byte, len(commit.Signatures))
-	)
-
-	bv, ok := batch.CreateBatchVerifier(vals.GetProposer().PubKey)
-	if ok && len(commit.Signatures) > 1 {
-		for idx, commitSig := range commit.Signatures {
-			if commitSig.Absent() {
-				continue // OK, some signatures can be absent.
-			}
-
-			// The vals and commit have a 1-to-1 correspondance.
-			// This means we don't need the validator address or to do any lookup.
-			val := vals.Validators[idx]
-
-			// Validate signature.
-			voteSignBytes := commit.VoteSignBytes(chainID, int32(idx))
-			// cache the signBytes in case batch verification fails
-			cacheSignBytes[string(val.PubKey.Bytes())] = voteSignBytes
-			// add the key, sig and message to the verifier
-			if err := bv.Add(val.PubKey, voteSignBytes, commitSig.Signature); err != nil {
-				return err
-			}
-
-			// Good!
-			if commitSig.ForBlock() {
-				talliedVotingPower += val.VotingPower
-			}
-		}
-		if !bv.Verify() {
-			talliedVotingPower, err = verifyCommitSingle(chainID, vals, commit, cacheSignBytes)
-			if err != nil {
-				return err
-			}
-		}
-	} else {
-		talliedVotingPower, err = verifyCommitSingle(chainID, vals, commit, cacheSignBytes)
-		if err != nil {
-			return err
-		}
-	}
-
-	if got, needed := talliedVotingPower, votingPowerNeeded; got <= needed {
-		return ErrNotEnoughVotingPowerSigned{Got: got, Needed: needed}
-	}
-
-	return nil
+	return VerifyCommit(chainID, vals, blockID, height, commit)
 }
 
 // LIGHT CLIENT VERIFICATION METHODS
 
 // VerifyCommitLight verifies +2/3 of the set had signed the given commit.
-//
-// This method is primarily used by the light client and does not check all the
-// signatures.
 func (vals *ValidatorSet) VerifyCommitLight(chainID string, blockID BlockID,
 	height int64, commit *Commit) error {
-	if commit == nil {
-		return errors.New("nil commit")
-	}
-
-	if vals.Size() != len(commit.Signatures) {
-		return NewErrInvalidCommitSignatures(vals.Size(), len(commit.Signatures))
-	}
-
-	// Validate Height and BlockID.
-	if height != commit.Height {
-		return NewErrInvalidCommitHeight(height, commit.Height)
-	}
-	if !blockID.Equals(commit.BlockID) {
-		return fmt.Errorf("invalid commit -- wrong block ID: want %v, got %v",
-			blockID, commit.BlockID)
-	}
-
-	talliedVotingPower := int64(0)
-	votingPowerNeeded := vals.TotalVotingPower() * 2 / 3
-	cacheSignBytes := make(map[string][]byte, len(commit.Signatures))
-	var err error
-
-	// need to check if batch verification is supported
-	// if batch is supported and the there are more than x key(s) run batch, otherwise run single.
-	// if batch verification fails reset tally votes to 0 and single verify until we have 2/3+
-	// check if the key supports batch verification
-	bv, ok := batch.CreateBatchVerifier(vals.GetProposer().PubKey)
-	if ok && len(commit.Signatures) > 1 {
-		for idx, commitSig := range commit.Signatures {
-			// No need to verify absent or nil votes.
-			if !commitSig.ForBlock() {
-				continue
-			}
-
-			// The vals and commit have a 1-to-1 correspondance.
-			// This means we don't need the validator address or to do any lookup.
-			val := vals.Validators[idx]
-			voteSignBytes := commit.VoteSignBytes(chainID, int32(idx))
-			cacheSignBytes[string(val.PubKey.Bytes())] = voteSignBytes
-			// add the key, sig and message to the verifier
-			if err := bv.Add(val.PubKey, voteSignBytes, commitSig.Signature); err != nil {
-				return err
-			}
-
-			talliedVotingPower += val.VotingPower
-
-			// return as soon as +2/3 of the signatures are verified
-			if talliedVotingPower > votingPowerNeeded {
-				return nil
-			}
-		}
-
-		if !bv.Verify() {
-			// reset talliedVotingPower to verify enough signatures to meet the 2/3+ threshold
-			talliedVotingPower, err = verifyCommitLightSingle(
-				chainID, vals, commit, votingPowerNeeded, cacheSignBytes)
-			if err != nil {
-				return err
-			} else if talliedVotingPower > votingPowerNeeded {
-				return nil
-			}
-		}
-	} else {
-		talliedVotingPower, err = verifyCommitLightSingle(
-			chainID, vals, commit, votingPowerNeeded, cacheSignBytes)
-		if err != nil {
-			return err
-		} else if talliedVotingPower > votingPowerNeeded {
-			return nil
-		}
-	}
-	return ErrNotEnoughVotingPowerSigned{Got: talliedVotingPower, Needed: votingPowerNeeded}
+	return VerifyCommitLight(chainID, vals, blockID, height, commit)
 }
 
 // VerifyCommitLightTrusting verifies that trustLevel of the validator set signed
 // this commit.
-//
-// NOTE the given validators do not necessarily correspond to the validator set
-// for this commit, but there may be some intersection.
-//
-// This method is primarily used by the light client and does not check all the
-// signatures.
 func (vals *ValidatorSet) VerifyCommitLightTrusting(chainID string, commit *Commit, trustLevel tmmath.Fraction) error {
-	// sanity checks
-	if trustLevel.Denominator == 0 {
-		return errors.New("trustLevel has zero Denominator")
-	}
-	if commit == nil {
-		return errors.New("nil commit")
-	}
-
-	var (
-		talliedVotingPower int64
-		seenVals           = make(map[int32]int, len(commit.Signatures)) // validator index -> commit index
-		err                error
-		cacheSignBytes     = make(map[string][]byte, len(commit.Signatures))
-	)
-
-	// Safely calculate voting power needed.
-	totalVotingPowerMulByNumerator, overflow := safeMul(vals.TotalVotingPower(), int64(trustLevel.Numerator))
-	if overflow {
-		return errors.New("int64 overflow while calculating voting power needed. please provide smaller trustLevel numerator")
-	}
-	votingPowerNeeded := totalVotingPowerMulByNumerator / int64(trustLevel.Denominator)
-
-	bv, ok := batch.CreateBatchVerifier(vals.GetProposer().PubKey)
-	if ok && len(commit.Signatures) > 1 {
-		for idx, commitSig := range commit.Signatures {
-			// No need to verify absent or nil votes.
-			if !commitSig.ForBlock() {
-				continue
-			}
-
-			// We don't know the validators that committed this block, so we have to
-			// check for each vote if its validator is already known.
-			valIdx, val := vals.GetByAddress(commitSig.ValidatorAddress)
-
-			if val != nil {
-				// check for double vote of validator on the same commit
-				if firstIndex, ok := seenVals[valIdx]; ok {
-					secondIndex := idx
-					return fmt.Errorf("double vote from %v (%d and %d)", val, firstIndex, secondIndex)
-				}
-				seenVals[valIdx] = idx
-
-				// Validate signature.
-				voteSignBytes := commit.VoteSignBytes(chainID, int32(idx))
-				// cache the signed bytes in case we fail verification
-				cacheSignBytes[string(val.PubKey.Bytes())] = voteSignBytes
-				// if batch verification is supported add the key, sig and message to the verifier
-				if err := bv.Add(val.PubKey, voteSignBytes, commitSig.Signature); err != nil {
-					return err
-				}
-
-				talliedVotingPower += val.VotingPower
-
-				if talliedVotingPower > votingPowerNeeded {
-					return nil
-				}
-			}
-		}
-		if !bv.Verify() {
-			talliedVotingPower, err = verifyCommitLightTrustingSingle(
-				chainID, vals, commit, votingPowerNeeded, cacheSignBytes)
-			if err != nil {
-				return err
-			} else if talliedVotingPower > votingPowerNeeded {
-				return nil
-			}
-		}
-	} else {
-		talliedVotingPower, err = verifyCommitLightTrustingSingle(
-			chainID, vals, commit, votingPowerNeeded, cacheSignBytes)
-		if err != nil {
-			return err
-		} else if talliedVotingPower > votingPowerNeeded {
-			return nil
-		}
-	}
-
-	return ErrNotEnoughVotingPowerSigned{Got: talliedVotingPower, Needed: votingPowerNeeded}
+	return VerifyCommitLightTrusting(chainID, vals, commit, trustLevel)
 }
 
 // findPreviousProposer reverses the compare proposer priority function to find the validator
@@ -1160,127 +931,3 @@ func safeMul(a, b int64) (int64, bool) {
 
 	return a * b, false
 }
-
-// verifyCommitLightTrustingSingle single verifies commits
-// If a key does not support batch verification, or batch verification fails this will be used
-// This method is used for light clients, it only checks 2/3+ of the signatures
-func verifyCommitLightTrustingSingle(
-	chainID string, vals *ValidatorSet, commit *Commit, votingPowerNeeded int64,
-	cachedVals map[string][]byte) (int64, error) {
-	var (
-		seenVals                 = make(map[int32]int, len(commit.Signatures))
-		talliedVotingPower int64 = 0
-	)
-	for idx, commitSig := range commit.Signatures {
-		// No need to verify absent or nil votes.
-		if !commitSig.ForBlock() {
-			continue
-		}
-
-		var voteSignBytes []byte
-
-		// We don't know the validators that committed this block, so we have to
-		// check for each vote if its validator is already known.
-		valIdx, val := vals.GetByAddress(commitSig.ValidatorAddress)
-
-		if val != nil {
-			// check for double vote of validator on the same commit
-			if firstIndex, ok := seenVals[valIdx]; ok {
-				secondIndex := idx
-				return 0, fmt.Errorf("double vote from %v (%d and %d)", val, firstIndex, secondIndex)
-			}
-			seenVals[valIdx] = idx
-
-			// Validate signature.
-			// voteSignBytes := commit.VoteSignBytes(chainID, int32(idx))
-			if val, ok := cachedVals[string(val.PubKey.Bytes())]; !ok {
-				voteSignBytes = commit.VoteSignBytes(chainID, int32(idx))
-			} else {
-				voteSignBytes = val
-			}
-			if !val.PubKey.VerifySignature(voteSignBytes, commitSig.Signature) {
-				return 0, fmt.Errorf("wrong signature (#%d): %X", idx, commitSig.Signature)
-			}
-
-			talliedVotingPower += val.VotingPower
-
-			if talliedVotingPower > votingPowerNeeded {
-				return talliedVotingPower, nil
-			}
-		}
-	}
-	return talliedVotingPower, nil
-}
-
-// verifyCommitLightSingle single verifies commits.
-// If a key does not support batch verification, or batch verification fails this will be used
-// This method is used for light client and block sync verification, it will only check 2/3+ signatures
-func verifyCommitLightSingle(
-	chainID string, vals *ValidatorSet, commit *Commit, votingPowerNeeded int64,
-	cachedVals map[string][]byte) (int64, error) {
-	var talliedVotingPower int64 = 0
-	for idx, commitSig := range commit.Signatures {
-		// No need to verify absent or nil votes.
-		if !commitSig.ForBlock() {
-			continue
-		}
-
-		// The vals and commit have a 1-to-1 correspondance.
-		// This means we don't need the validator address or to do any lookup.
-		var voteSignBytes []byte
-		val := vals.Validators[idx]
-
-		// Check if we have the validator in the cache
-		if val, ok := cachedVals[string(val.PubKey.Bytes())]; !ok {
-			voteSignBytes = commit.VoteSignBytes(chainID, int32(idx))
-		} else {
-			voteSignBytes = val
-		}
-		// Validate signature.
-		if !val.PubKey.VerifySignature(voteSignBytes, commitSig.Signature) {
-			return 0, fmt.Errorf("wrong signature (#%d): %X", idx, commitSig.Signature)
-		}
-
-		talliedVotingPower += val.VotingPower
-
-		// return as soon as +2/3 of the signatures are verified
-		if talliedVotingPower > votingPowerNeeded {
-			return talliedVotingPower, nil
-		}
-	}
-	return talliedVotingPower, nil
-}
-
-// verifyCommitSingle single verifies commits.
-// If a key does not support batch verification, or batch verification fails this will be used
-// This method is used to check all the signatures included in a commit.
-// It is used in consensus for validating a block LastCommit.
-func verifyCommitSingle(chainID string, vals *ValidatorSet, commit *Commit,
-	cachedVals map[string][]byte) (int64, error) {
-	var talliedVotingPower int64 = 0
-	for idx, commitSig := range commit.Signatures {
-		if commitSig.Absent() {
-			continue // OK, some signatures can be absent.
-		}
-
-		var voteSignBytes []byte
-		val := vals.Validators[idx]
-
-		// Check if we have the validator in the cache
-		if val, ok := cachedVals[string(val.PubKey.Bytes())]; !ok {
-			voteSignBytes = commit.VoteSignBytes(chainID, int32(idx))
-		} else {
-			voteSignBytes = val
-		}
-
-		if !val.PubKey.VerifySignature(voteSignBytes, commitSig.Signature) {
-			return talliedVotingPower, fmt.Errorf("wrong signature (#%d): %X", idx, commitSig.Signature)
-		}
-
-		// Good!
-		if commitSig.ForBlock() {
-			talliedVotingPower += val.VotingPower
-		}
-	}
-	return talliedVotingPower, nil
-}
diff --git a/types/validator_set_test.go b/types/validator_set_test.go
index f3f4552e7..1f5d7d82e 100644
--- a/types/validator_set_test.go
+++ b/types/validator_set_test.go
@@ -679,155 +679,6 @@ func TestSafeSubClip(t *testing.T) {
 
 //-------------------------------------------------------------------
 
-// Check VerifyCommit, VerifyCommitLight and VerifyCommitLightTrusting basic
-// verification.
-func TestValidatorSet_VerifyCommit_All(t *testing.T) {
-	var (
-		privKey = ed25519.GenPrivKey()
-		pubKey  = privKey.PubKey()
-		v1      = NewValidator(pubKey, 1000)
-		vset    = NewValidatorSet([]*Validator{v1})
-
-		chainID = "Lalande21185"
-	)
-
-	vote := examplePrecommit()
-	vote.ValidatorAddress = pubKey.Address()
-	v := vote.ToProto()
-	sig, err := privKey.Sign(VoteSignBytes(chainID, v))
-	require.NoError(t, err)
-	vote.Signature = sig
-
-	commit := NewCommit(vote.Height, vote.Round, vote.BlockID, []CommitSig{vote.CommitSig()})
-
-	vote2 := *vote
-	sig2, err := privKey.Sign(VoteSignBytes("EpsilonEridani", v))
-	require.NoError(t, err)
-	vote2.Signature = sig2
-
-	testCases := []struct {
-		description string
-		chainID     string
-		blockID     BlockID
-		height      int64
-		commit      *Commit
-		expErr      bool
-	}{
-		{"good", chainID, vote.BlockID, vote.Height, commit, false},
-
-		{"wrong signature (#0)", "EpsilonEridani", vote.BlockID, vote.Height, commit, true},
-		{"wrong block ID", chainID, makeBlockIDRandom(), vote.Height, commit, true},
-		{"wrong height", chainID, vote.BlockID, vote.Height - 1, commit, true},
-
-		{"wrong set size: 1 vs 0", chainID, vote.BlockID, vote.Height,
-			NewCommit(vote.Height, vote.Round, vote.BlockID, []CommitSig{}), true},
-
-		{"wrong set size: 1 vs 2", chainID, vote.BlockID, vote.Height,
-			NewCommit(vote.Height, vote.Round, vote.BlockID,
-				[]CommitSig{vote.CommitSig(), {BlockIDFlag: BlockIDFlagAbsent}}), true},
-
-		{"insufficient voting power: got 0, needed more than 666", chainID, vote.BlockID, vote.Height,
-			NewCommit(vote.Height, vote.Round, vote.BlockID, []CommitSig{{BlockIDFlag: BlockIDFlagAbsent}}), true},
-
-		{"wrong signature (#0)", chainID, vote.BlockID, vote.Height,
-			NewCommit(vote.Height, vote.Round, vote.BlockID, []CommitSig{vote2.CommitSig()}), true},
-	}
-
-	for _, tc := range testCases {
-		tc := tc
-		t.Run(tc.description, func(t *testing.T) {
-			err := vset.VerifyCommit(tc.chainID, tc.blockID, tc.height, tc.commit)
-			if tc.expErr {
-				if assert.Error(t, err, "VerifyCommit") {
-					assert.Contains(t, err.Error(), tc.description, "VerifyCommit")
-				}
-			} else {
-				assert.NoError(t, err, "VerifyCommit")
-			}
-
-			err = vset.VerifyCommitLight(tc.chainID, tc.blockID, tc.height, tc.commit)
-			if tc.expErr {
-				if assert.Error(t, err, "VerifyCommitLight") {
-					assert.Contains(t, err.Error(), tc.description, "VerifyCommitLight")
-				}
-			} else {
-				assert.NoError(t, err, "VerifyCommitLight")
-			}
-		})
-	}
-}
-
-func TestValidatorSet_VerifyCommit_CheckAllSignatures(t *testing.T) {
-	var (
-		chainID = "test_chain_id"
-		h       = int64(3)
-		blockID = makeBlockIDRandom()
-	)
-
-	voteSet, valSet, vals := randVoteSet(h, 0, tmproto.PrecommitType, 4, 10)
-	commit, err := makeCommit(blockID, h, 0, voteSet, vals, time.Now())
-	require.NoError(t, err)
-
-	// malleate 4th signature
-	vote := voteSet.GetByIndex(3)
-	v := vote.ToProto()
-	err = vals[3].SignVote(context.Background(), "CentaurusA", v)
-	require.NoError(t, err)
-	vote.Signature = v.Signature
-	commit.Signatures[3] = vote.CommitSig()
-
-	err = valSet.VerifyCommit(chainID, blockID, h, commit)
-	if assert.Error(t, err) {
-		assert.Contains(t, err.Error(), "wrong signature (#3)")
-	}
-}
-
-func TestValidatorSet_VerifyCommitLight_ReturnsAsSoonAsMajorityOfVotingPowerSigned(t *testing.T) {
-	var (
-		chainID = "test_chain_id"
-		h       = int64(3)
-		blockID = makeBlockIDRandom()
-	)
-
-	voteSet, valSet, vals := randVoteSet(h, 0, tmproto.PrecommitType, 4, 10)
-	commit, err := makeCommit(blockID, h, 0, voteSet, vals, time.Now())
-	require.NoError(t, err)
-
-	// malleate 4th signature (3 signatures are enough for 2/3+)
-	vote := voteSet.GetByIndex(3)
-	v := vote.ToProto()
-	err = vals[3].SignVote(context.Background(), "CentaurusA", v)
-	require.NoError(t, err)
-	vote.Signature = v.Signature
-	commit.Signatures[3] = vote.CommitSig()
-
-	err = valSet.VerifyCommitLight(chainID, blockID, h, commit)
-	assert.NoError(t, err)
-}
-
-func TestValidatorSet_VerifyCommitLightTrusting_ReturnsAsSoonAsTrustLevelOfVotingPowerSigned(t *testing.T) {
-	var (
-		chainID = "test_chain_id"
-		h       = int64(3)
-		blockID = makeBlockIDRandom()
-	)
-
-	voteSet, valSet, vals := randVoteSet(h, 0, tmproto.PrecommitType, 4, 10)
-	commit, err := makeCommit(blockID, h, 0, voteSet, vals, time.Now())
-	require.NoError(t, err)
-
-	// malleate 3rd signature (2 signatures are enough for 1/3+ trust level)
-	vote := voteSet.GetByIndex(2)
-	v := vote.ToProto()
-	err = vals[2].SignVote(context.Background(), "CentaurusA", v)
-	require.NoError(t, err)
-	vote.Signature = v.Signature
-	commit.Signatures[2] = vote.CommitSig()
-
-	err = valSet.VerifyCommitLightTrusting(chainID, commit, tmmath.Fraction{Numerator: 1, Denominator: 3})
-	assert.NoError(t, err)
-}
-
 func TestEmptySet(t *testing.T) {
 
 	var valList []*Validator
@@ -1531,62 +1382,6 @@ func TestValSetUpdateOverflowRelated(t *testing.T) {
 	}
 }
 
-func TestValidatorSet_VerifyCommitLightTrusting(t *testing.T) {
-	var (
-		blockID                       = makeBlockIDRandom()
-		voteSet, originalValset, vals = randVoteSet(1, 1, tmproto.PrecommitType, 6, 1)
-		commit, err                   = makeCommit(blockID, 1, 1, voteSet, vals, time.Now())
-		newValSet, _                  = randValidatorPrivValSet(2, 1)
-	)
-	require.NoError(t, err)
-
-	testCases := []struct {
-		valSet *ValidatorSet
-		err    bool
-	}{
-		// good
-		0: {
-			valSet: originalValset,
-			err:    false,
-		},
-		// bad - no overlap between validator sets
-		1: {
-			valSet: newValSet,
-			err:    true,
-		},
-		// good - first two are different but the rest of the same -> >1/3
-		2: {
-			valSet: NewValidatorSet(append(newValSet.Validators, originalValset.Validators...)),
-			err:    false,
-		},
-	}
-
-	for _, tc := range testCases {
-		err = tc.valSet.VerifyCommitLightTrusting("test_chain_id", commit,
-			tmmath.Fraction{Numerator: 1, Denominator: 3})
-		if tc.err {
-			assert.Error(t, err)
-		} else {
-			assert.NoError(t, err)
-		}
-	}
-}
-
-func TestValidatorSet_VerifyCommitLightTrustingErrorsOnOverflow(t *testing.T) {
-	var (
-		blockID               = makeBlockIDRandom()
-		voteSet, valSet, vals = randVoteSet(1, 1, tmproto.PrecommitType, 1, MaxTotalVotingPower)
-		commit, err           = makeCommit(blockID, 1, 1, voteSet, vals, time.Now())
-	)
-	require.NoError(t, err)
-
-	err = valSet.VerifyCommitLightTrusting("test_chain_id", commit,
-		tmmath.Fraction{Numerator: 25, Denominator: 55})
-	if assert.Error(t, err) {
-		assert.Contains(t, err.Error(), "int64 overflow")
-	}
-}
-
 func TestSafeMul(t *testing.T) {
 	testCases := []struct {
 		a        int64