diff --git a/third_party/blink/renderer/modules/accessibility/ax_object_cache_impl.cc b/third_party/blink/renderer/modules/accessibility/ax_object_cache_impl.cc
index 8bf69a5878dfba..d1384f5ead2614 100644
--- a/third_party/blink/renderer/modules/accessibility/ax_object_cache_impl.cc
+++ b/third_party/blink/renderer/modules/accessibility/ax_object_cache_impl.cc
@@ -719,9 +719,13 @@ void AXObjectCacheImpl::UpdateLifecycleIfNeeded(Document& document) {
 }
 
 void AXObjectCacheImpl::UpdateAXForAllDocuments() {
+#if DCHECK_IS_ON()
   DCHECK(!IsFrozen())
       << "Don't call UpdateAXForAllDocuments() here; layout and a11y are "
          "already clean at the start of serialization.";
+  DCHECK(!updating_layout_and_ax_) << "Undesirable recursion.";
+  base::AutoReset<bool> updating(&updating_layout_and_ax_, true);
+#endif
 
   // First update the layout for the main and popup document.
   UpdateLifecycleIfNeeded(GetDocument());
@@ -2466,11 +2470,7 @@ void AXObjectCacheImpl::ProcessDeferredAccessibilityEvents(Document& document) {
 
   DCHECK_EQ(document, GetDocument());
 
-  if (processing_deferred_events_) {
-    // TODO(aleventhal) Perhaps the caller should be responsible for this:
-    // consider changing to a DCHECK.
-    return;
-  }
+  DCHECK(!processing_deferred_events_);
 
   if (IsDirty()) {
     if (GetPopupDocumentIfShowing()) {
@@ -2915,7 +2915,6 @@ void AXObjectCacheImpl::FireAXEventImmediately(
     ax::mojom::blink::Action event_from_action,
     const BlinkAXEventIntentsSet& event_intents) {
 #if DCHECK_IS_ON()
-  DCHECK(processing_deferred_events_);
   // Make sure none of the layout views are in the process of being laid out.
   // Notifications should only be sent after the layoutObject has finished
   auto* ax_layout_object = DynamicTo<AXLayoutObject>(obj);
diff --git a/third_party/blink/renderer/modules/accessibility/ax_object_cache_impl.h b/third_party/blink/renderer/modules/accessibility/ax_object_cache_impl.h
index 8dec26293c0c86..09ed6f79016ad7 100644
--- a/third_party/blink/renderer/modules/accessibility/ax_object_cache_impl.h
+++ b/third_party/blink/renderer/modules/accessibility/ax_object_cache_impl.h
@@ -670,6 +670,9 @@ class MODULES_EXPORT AXObjectCacheImpl
   std::unique_ptr<AXRelationCache> relation_cache_;
 
   bool processing_deferred_events_ = false;
+#if DCHECK_IS_ON()
+  bool updating_layout_and_ax_ = false;
+#endif
 
   // Verified when finalizing.
   bool has_been_disposed_ = false;