diff --git a/cmd/gerritbot/gerritbot.go b/cmd/gerritbot/gerritbot.go
index 45b9a49..893b205 100644
--- a/cmd/gerritbot/gerritbot.go
+++ b/cmd/gerritbot/gerritbot.go
@@ -831,7 +831,7 @@
 	resp, err := b.githubClient.Do(ctx, req, pr)
 	logGitHubRateLimits(resp)
 	if err != nil {
-		if resp.StatusCode == http.StatusNotModified {
+		if resp != nil && resp.StatusCode == http.StatusNotModified {
 			log.Println("Returning cached version of", shortLink)
 			return cpr.pr, nil
 		}