--- a/hghooks/mozhghooks/check/prevent_ftl_changes.py
+++ b/hghooks/mozhghooks/check/prevent_ftl_changes.py
@@ -45,31 +45,34 @@ class FTLCheck(PreTxnChangegroupCheck):
     @property
     def name(self):
         return 'ftl_check'
 
     def relevant(self):
         return self.repo_metadata['firefox_releasing']
 
     def pre(self):
-        pass
+        self.mergeOrBackout = False
 
     def check(self, ctx):
-        if len(ctx.parents()) > 1:
-            # Skip merge changesets
-            return True
-
-        if is_backout(ctx.description()):
-            # Ignore backouts
-            return True
-
-        if any(f.endswith('.ftl') for f in ctx.files()):
-            requal = parse_requal_reviewers(ctx.description())
-            reviewers = [nick for (name, nick) in FTL_DRIVERS]
-            if any(nick in reviewers for nick in requal):
+        if not self.mergeOrBackout:
+            if len(ctx.parents()) > 1:
+                # Skip merge changesets
+                self.mergeOrBackout = True
                 return True
 
-            print_banner(self.ui, 'error', FTL_COMMIT_FOUND)
-            return False
+            if is_backout(ctx.description()):
+                # Ignore backouts
+                self.mergeOrBackout = True
+                return True
+
+            if any(f.endswith('.ftl') for f in ctx.files()):
+                requal = parse_requal_reviewers(ctx.description())
+                reviewers = [nick for (name, nick) in FTL_DRIVERS]
+                if any(nick in reviewers for nick in requal):
+                    return True
+
+                print_banner(self.ui, 'error', FTL_COMMIT_FOUND)
+                return False
         return True
 
     def post_check(self):
         return True