diff --git a/lib/jasmine-core/jasmine.js b/lib/jasmine-core/jasmine.js
index 790ed107..64489099 100644
--- a/lib/jasmine-core/jasmine.js
+++ b/lib/jasmine-core/jasmine.js
@@ -294,9 +294,21 @@ getJasmineRequireObj().base = function(j$, jasmineGlobal) {
   };
 
   j$.isError_ = function(value) {
+    if (!value) {
+      return false;
+    }
+
     if (value instanceof Error) {
       return true;
     }
+    if (
+      typeof window !== 'undefined' &&
+      typeof window.trustedTypes !== 'undefined'
+    ) {
+      return (
+        typeof value.stack === 'string' && typeof value.message === 'string'
+      );
+    }
     if (value && value.constructor && value.constructor.constructor) {
       var valueGlobal = value.constructor.constructor('return this');
       if (j$.isFunction_(valueGlobal)) {
diff --git a/spec/core/baseSpec.js b/spec/core/baseSpec.js
index 51b90063..dd5dd225 100644
--- a/spec/core/baseSpec.js
+++ b/spec/core/baseSpec.js
@@ -29,6 +29,43 @@ describe('base helpers', function() {
         }
       }, 100);
     });
+
+    it('returns true for an Error subclass', function() {
+      function MyError() {}
+      MyError.prototype = new Error();
+      expect(jasmineUnderTest.isError_(new MyError())).toBe(true);
+    });
+
+    it('returns true for an un-thrown Error with no message in this environment', function() {
+      expect(jasmineUnderTest.isError_(new Error())).toBe(true);
+    });
+
+    it('returns true for an Error that originated from another frame', function() {
+      var iframe, error;
+
+      if (typeof window === 'undefined') {
+        pending('This test only runs in browsers.');
+      }
+
+      iframe = document.createElement('iframe');
+      iframe.style.display = 'none';
+      document.body.appendChild(iframe);
+
+      try {
+        error = iframe.contentWindow.eval('new Error()');
+        expect(jasmineUnderTest.isError_(error)).toBe(true);
+      } finally {
+        document.body.removeChild(iframe);
+      }
+    });
+
+    it('returns false for a falsy value', function() {
+      expect(jasmineUnderTest.isError_(undefined)).toBe(false);
+    });
+
+    it('returns false for a non-Error object', function() {
+      expect(jasmineUnderTest.isError_({})).toBe(false);
+    });
   });
 
   describe('isAsymmetricEqualityTester_', function() {
diff --git a/src/core/base.js b/src/core/base.js
index c40c6559..89cd2b6e 100644
--- a/src/core/base.js
+++ b/src/core/base.js
@@ -99,9 +99,21 @@ getJasmineRequireObj().base = function(j$, jasmineGlobal) {
   };
 
   j$.isError_ = function(value) {
+    if (!value) {
+      return false;
+    }
+
     if (value instanceof Error) {
       return true;
     }
+    if (
+      typeof window !== 'undefined' &&
+      typeof window.trustedTypes !== 'undefined'
+    ) {
+      return (
+        typeof value.stack === 'string' && typeof value.message === 'string'
+      );
+    }
     if (value && value.constructor && value.constructor.constructor) {
       var valueGlobal = value.constructor.constructor('return this');
       if (j$.isFunction_(valueGlobal)) {