diff --git a/smx509/pkcs8.go b/smx509/pkcs8.go
index 31f3ff1..1ce4c44 100644
--- a/smx509/pkcs8.go
+++ b/smx509/pkcs8.go
@@ -54,7 +54,7 @@ func ParsePKCS8PrivateKey(der []byte) (key interface{}, err error) {
 	} else {
 		key = ecKey
 	}
-	return key, nil
+	return key, err
 }
 
 // MarshalPKCS8PrivateKey converts a private key to PKCS#8, ASN.1 DER form.