diff --git a/packages/ui/components/overlays/src/OverlayController.js b/packages/ui/components/overlays/src/OverlayController.js
index 9b1b7b9a5..99991fd27 100644
--- a/packages/ui/components/overlays/src/OverlayController.js
+++ b/packages/ui/components/overlays/src/OverlayController.js
@@ -640,7 +640,7 @@ export class OverlayController extends EventTarget {
   __setupTeardownAccessibility({ phase }) {
     if (phase === 'init') {
       this.__storeOriginalAttrs(this.contentNode, ['role', 'id']);
-      const isModal = this.hasBackdrop;
+      const isModal = this.trapsKeyboardFocus;
 
       if (this.invokerNode) {
         const attributesToStore = ['aria-labelledby', 'aria-describedby'];
@@ -1300,7 +1300,7 @@ export class OverlayController extends EventTarget {
     if (phase === 'init' || phase === 'teardown') {
       this.__setupTeardownAccessibility({ phase });
     }
-    const isModal = this.hasBackdrop;
+    const isModal = this.trapsKeyboardFocus;
     if (this.invokerNode && !this.isTooltip && !isModal) {
       this.invokerNode.setAttribute('aria-expanded', `${phase === 'show'}`);
     }
diff --git a/packages/ui/components/overlays/test/OverlayController.test.js b/packages/ui/components/overlays/test/OverlayController.test.js
index 2de9620c9..898adbe40 100644
--- a/packages/ui/components/overlays/test/OverlayController.test.js
+++ b/packages/ui/components/overlays/test/OverlayController.test.js
@@ -1534,7 +1534,7 @@ describe('OverlayController', () => {
       );
       const ctrl = new OverlayController({
         ...withLocalTestConfig(),
-        hasBackdrop: true,
+        trapsKeyboardFocus: true,
         handlesAccessibility: true,
         invokerNode,
       });