diff --git a/server/middleware.go b/server/middleware.go
index 8a0f9b4..16f152d 100644
--- a/server/middleware.go
+++ b/server/middleware.go
@@ -114,6 +114,10 @@ func assertServerToken(key *rsa.PublicKey, serverToken string) (*peering.ServerT
 	}
 	token, err := jwt.ParseWithClaims(serverToken, &peering.ServerTokenClaims{}, fn)
 	if err != nil {
+		validationError, ok := err.(*jwt.ValidationError)
+		if ok {
+			return nil, validationError.Inner
+		}
 		return nil, err
 	}
 	if !token.Valid {
@@ -146,6 +150,10 @@ func assertClientToken(peerID peering.PeerID, store peering.Store, clientToken s
 	}
 	token, err := jwt.ParseWithClaims(clientToken, &peering.ClientTokenClaims{}, fn)
 	if err != nil {
+		validationError, ok := err.(*jwt.ValidationError)
+		if ok {
+			return nil, validationError.Inner
+		}
 		return nil, err
 	}
 	if !token.Valid {