diff --git a/spec/unit/rust-crypto/rust-crypto.spec.ts b/spec/unit/rust-crypto/rust-crypto.spec.ts
index fe8da0f26c0..07501a47c95 100644
--- a/spec/unit/rust-crypto/rust-crypto.spec.ts
+++ b/spec/unit/rust-crypto/rust-crypto.spec.ts
@@ -1376,6 +1376,41 @@ describe("RustCrypto", () => {
         });
     });
 
+    describe("pinCurrentIdentity", () => {
+        let rustCrypto: RustCrypto;
+        let olmMachine: Mocked<RustSdkCryptoJs.OlmMachine>;
+
+        beforeEach(() => {
+            olmMachine = {
+                getIdentity: jest.fn(),
+            } as unknown as Mocked<RustSdkCryptoJs.OlmMachine>;
+            rustCrypto = new RustCrypto(
+                logger,
+                olmMachine,
+                {} as MatrixClient["http"],
+                TEST_USER,
+                TEST_DEVICE_ID,
+                {} as ServerSideSecretStorage,
+                {} as CryptoCallbacks,
+            );
+        });
+
+        it("throws an error for an unknown user", async () => {
+            await expect(rustCrypto.pinCurrentUserIdentity("@alice:example.com")).rejects.toThrow(
+                "Cannot pin identity of unknown user",
+            );
+        });
+
+        it("throws an error for our own user", async () => {
+            const ownIdentity = new RustSdkCryptoJs.OwnUserIdentity();
+            olmMachine.getIdentity.mockResolvedValue(ownIdentity);
+
+            await expect(rustCrypto.pinCurrentUserIdentity("@alice:example.com")).rejects.toThrow(
+                "Cannot pin identity of own user",
+            );
+        });
+    });
+
     describe("key backup", () => {
         it("is started when rust crypto is created", async () => {
             // `RustCrypto.checkKeyBackupAndEnable` async call is made in background in the RustCrypto constructor.