diff --git a/state/validator.go b/state/validator.go
index e16c6246a..20f12532e 100644
--- a/state/validator.go
+++ b/state/validator.go
@@ -56,6 +56,7 @@ type Validator struct {
 }
 
 // Creates a new copy of the validator so we can mutate accum.
+// Panics if the validator is nil.
 func (v *Validator) Copy() *Validator {
 	vCopy := *v
 	return &vCopy
@@ -83,6 +84,9 @@ func (v *Validator) CompareAccum(other *Validator) *Validator {
 }
 
 func (v *Validator) String() string {
+	if v == nil {
+		return "nil-Validator"
+	}
 	return fmt.Sprintf("Validator{%X %v %v-%v-%v VP:%v A:%v}",
 		v.Address,
 		v.PubKey,
diff --git a/state/validator_set.go b/state/validator_set.go
index 27f1c29da..7f821d9c1 100644
--- a/state/validator_set.go
+++ b/state/validator_set.go
@@ -112,6 +112,9 @@ func (valSet *ValidatorSet) TotalVotingPower() int64 {
 }
 
 func (valSet *ValidatorSet) Proposer() (proposer *Validator) {
+	if len(valSet.Validators) == 0 {
+		return nil
+	}
 	if valSet.proposer == nil {
 		for _, val := range valSet.Validators {
 			valSet.proposer = valSet.proposer.CompareAccum(val)
@@ -255,6 +258,9 @@ func (valSet *ValidatorSet) String() string {
 }
 
 func (valSet *ValidatorSet) StringIndented(indent string) string {
+	if valSet == nil {
+		return "nil-ValidatorSet"
+	}
 	valStrings := []string{}
 	valSet.Iterate(func(index int, val *Validator) bool {
 		valStrings = append(valStrings, val.String())