diff --git a/server/mock/tx.go b/server/mock/tx.go
index 750d6984d213..6774fb28145a 100644
--- a/server/mock/tx.go
+++ b/server/mock/tx.go
@@ -6,7 +6,6 @@ import (
 	"fmt"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
-	"github.com/cosmos/cosmos-sdk/x/auth"
 )
 
 // An sdk.Tx which is its own sdk.Msg.
@@ -56,10 +55,6 @@ func (tx kvstoreTx) GetSigners() []sdk.AccAddress {
 	return nil
 }
 
-func (tx kvstoreTx) GetSignatures() []auth.StdSignature {
-	return nil
-}
-
 // takes raw transaction bytes and decodes them into an sdk.Tx. An sdk.Tx has
 // all the signatures and can be used to authenticate.
 func decodeTx(txBytes []byte) (sdk.Tx, sdk.Error) {