diff --git a/credentials/oauth/persistent_auth.go b/credentials/oauth/persistent_auth.go
index 1c5b6683..545f61fc 100644
--- a/credentials/oauth/persistent_auth.go
+++ b/credentials/oauth/persistent_auth.go
@@ -151,13 +151,6 @@ func NewPersistentAuth(ctx context.Context, opts ...PersistentAuthOption) (*Pers
 	return p, nil
 }
 
-// tokenErrorResponse is the response from the OAuth2 token endpoint when an
-// error occurs.
-type tokenErrorResponse struct {
-	Error            string `json:"error"`
-	ErrorDescription string `json:"error_description"`
-}
-
 // Load loads the OAuth2 token for the given OAuthArgument from the cache. If
 // the token is expired, it is refreshed using the refresh token.
 func (a *PersistentAuth) Load(ctx context.Context, arg OAuthArgument) (t *oauth2.Token, err error) {