diff --git a/blockchain/reactor_test.go b/blockchain/reactor_test.go
index d3e341644..a84051291 100644
--- a/blockchain/reactor_test.go
+++ b/blockchain/reactor_test.go
@@ -112,7 +112,7 @@ func makeBlock(height int64, state *sm.State) *types.Block {
 	block, _ := types.MakeBlock(height, "test_chain", makeTxs(height),
 		state.LastBlockTotalTx, new(types.Commit),
 		prevBlockID, valHash, state.AppHash,
-		state.Params.Hash(),
+		state.LastConsensusHash,
 		state.Params.BlockGossipParams.BlockPartSizeBytes)
 	return block
 }
diff --git a/consensus/state.go b/consensus/state.go
index 1018d3704..8187ea72f 100644
--- a/consensus/state.go
+++ b/consensus/state.go
@@ -866,7 +866,7 @@ func (cs *ConsensusState) createProposalBlock() (block *types.Block, blockParts
 	return types.MakeBlock(cs.Height, cs.state.ChainID, txs,
 		cs.state.LastBlockTotalTx, commit,
 		cs.state.LastBlockID, cs.state.Validators.Hash(),
-		cs.state.AppHash, cs.state.Params.Hash(),
+		cs.state.AppHash, cs.state.LastConsensusHash,
 		cs.state.Params.BlockPartSizeBytes)
 }
 
diff --git a/state/execution.go b/state/execution.go
index fbb0954d3..6f3266f6b 100644
--- a/state/execution.go
+++ b/state/execution.go
@@ -187,7 +187,7 @@ func (s *State) ValidateBlock(block *types.Block) error {
 func (s *State) validateBlock(block *types.Block) error {
 	// Basic block validation.
 	err := block.ValidateBasic(s.ChainID, s.LastBlockHeight,
-		s.LastBlockTotalTx, s.LastBlockID, s.LastBlockTime, s.AppHash, s.Params.Hash())
+		s.LastBlockTotalTx, s.LastBlockID, s.LastBlockTime, s.AppHash, s.LastConsensusHash)
 	if err != nil {
 		return err
 	}
diff --git a/state/execution_test.go b/state/execution_test.go
index 081a71e91..3080187b3 100644
--- a/state/execution_test.go
+++ b/state/execution_test.go
@@ -120,7 +120,7 @@ func makeBlock(height int64, state *State) *types.Block {
 	block, _ := types.MakeBlock(height, chainID,
 		makeTxs(height), state.LastBlockTotalTx,
 		new(types.Commit), prevBlockID, valHash,
-		state.AppHash, state.Params.Hash(), testPartSize)
+		state.AppHash, state.LastConsensusHash, testPartSize)
 	return block
 }
 
diff --git a/state/state.go b/state/state.go
index d3bca4a81..268e3ae90 100644
--- a/state/state.go
+++ b/state/state.go
@@ -59,6 +59,8 @@ type State struct {
 
 	// AppHash is updated after Commit
 	AppHash []byte
+	// LastConsensusHash is updated after Commit
+	LastConsensusHash []byte
 
 	logger log.Logger
 }
@@ -120,6 +122,7 @@ func (s *State) Copy() *State {
 		Validators:                  s.Validators.Copy(),
 		LastValidators:              s.LastValidators.Copy(),
 		AppHash:                     s.AppHash,
+		LastConsensusHash:           s.LastConsensusHash,
 		LastHeightValidatorsChanged: s.LastHeightValidatorsChanged,
 		logger:  s.logger,
 		ChainID: s.ChainID,
@@ -319,6 +322,7 @@ func (s *State) setBlockAndValidators(height int64,
 	s.LastBlockTime = blockTime
 	s.Validators = nextValSet
 	s.LastValidators = prevValSet
+	s.LastConsensusHash = s.Params.Hash()
 	s.Params = nextParams
 }
 
@@ -428,6 +432,7 @@ func MakeGenesisState(db dbm.DB, genDoc *types.GenesisDoc) (*State, error) {
 		Validators:                  types.NewValidatorSet(validators),
 		LastValidators:              types.NewValidatorSet(nil),
 		AppHash:                     genDoc.AppHash,
+		LastConsensusHash:           genDoc.ConsensusParams.Hash(),
 		LastHeightValidatorsChanged: 1,
 	}, nil
 }
diff --git a/types/block.go b/types/block.go
index 356776579..48b59027c 100644
--- a/types/block.go
+++ b/types/block.go
@@ -92,10 +92,6 @@ func (b *Block) ValidateBasic(chainID string, lastBlockHeight int64,
 	if !bytes.Equal(b.AppHash, appHash) {
 		return errors.New(cmn.Fmt("Wrong Block.Header.AppHash.  Expected %X, got %v", appHash, b.AppHash))
 	}
-	// TODO: make testing easier
-	if len(consensusHash) == 0 {
-		panic("food")
-	}
 	if !bytes.Equal(b.ConsensusHash, consensusHash) {
 		return errors.New(cmn.Fmt("Wrong Block.Header.ConsensusHash.  Expected %X, got %v", consensusHash, b.ConsensusHash))
 	}