diff --git a/rules.c b/rules.c
index 42c20bb1..303419d8 100644
--- a/rules.c
+++ b/rules.c
@@ -65,11 +65,11 @@ get_client_screen_from_rules(Client *c, Rule *rules)
 }
 
 Bool
-is_client_tag_from_rules(Client *c, Tag *t, Rule *r)
+is_tag_match_rules(Tag *t, Rule *r)
 {
     regmatch_t tmp;
 
-    if(!regexec(r->tagregex, t->name, 1, &tmp, 0))
+    if(r->tagregex && !regexec(r->tagregex, t->name, 1, &tmp, 0))
         return True;
 
     return False;
diff --git a/rules.h b/rules.h
index 116acb49..da160672 100644
--- a/rules.h
+++ b/rules.h
@@ -28,7 +28,7 @@
 
 Bool client_match_rule(Client *, Rule *);
 int get_client_screen_from_rules(Client *, Rule *);
-Bool is_client_tag_from_rules(Client *, Tag *, Rule *);
+Bool is_tag_match_rules(Tag *, Rule *);
 
 #endif
 // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99