diff --git a/__tests__/components/session-hooks-panel.test.tsx b/__tests__/components/session-hooks-panel.test.tsx
new file mode 100644
index 00000000..5750e412
--- /dev/null
+++ b/__tests__/components/session-hooks-panel.test.tsx
@@ -0,0 +1,102 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { render, screen } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import SessionHooksPanel from "@/app/components/session-hooks-panel";
+
+const mocks = vi.hoisted(() => ({
+  searchHookActivityAction: vi.fn(),
+  ChevronDown: (props: any) => <svg data-testid="chevron-icon" {...props} />,
+  ShieldCheck: () => <span data-testid="shield-check" />,
+  ShieldX: () => <span data-testid="shield-x" />,
+  ShieldAlert: () => <span data-testid="shield-alert" />,
+  Shield: () => <span data-testid="shield" />,
+  Copy: (props: any) => <span data-testid="copy-icon" {...props} />,
+  Check: (props: any) => <span data-testid="check-icon" {...props} />,
+  ChevronLeft: () => <span data-testid="chevron-left" />,
+  ChevronRight: () => <span data-testid="chevron-right" />,
+}));
+
+vi.mock("@/app/actions/get-hook-activity", () => ({
+  searchHookActivityAction: mocks.searchHookActivityAction,
+}));
+
+vi.mock("lucide-react", () => ({
+  ChevronDown: mocks.ChevronDown,
+  ShieldCheck: mocks.ShieldCheck,
+  ShieldX: mocks.ShieldX,
+  ShieldAlert: mocks.ShieldAlert,
+  Shield: mocks.Shield,
+  Copy: mocks.Copy,
+  Check: mocks.Check,
+}));
+
+vi.mock("@/contexts/AutoRefreshContext", () => ({
+  useAutoRefresh: () => ({ intervalSec: 0 }),
+}));
+
+vi.mock("@/lib/format-duration", () => ({
+  formatRelativeTime: () => "just now",
+}));
+
+const mockEntry = {
+  timestamp: Date.now(),
+  eventType: "PreToolUse",
+  integration: "claude",
+  toolName: "Read",
+  policyName: "test-policy",
+  policyNames: ["test-policy"],
+  decision: "allow" as const,
+  reason: "ok",
+  durationMs: 42,
+  sessionId: "sess_123",
+  permissionMode: "default",
+};
+
+const defaultPayload = {
+  entries: [mockEntry],
+  totalPages: 1,
+  page: 1,
+  stats: { totalEvents: 1, denyCount: 0, topPolicy: null, topPolicyCount: 0 },
+};
+
+describe("SessionHooksPanel", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mocks.searchHookActivityAction.mockResolvedValue(defaultPayload);
+  });
+
+  it("renders expand row button with correct aria attributes", () => {
+    render(<SessionHooksPanel sessionId="sess_123" initialData={defaultPayload} />);
+    const btn = screen.getByRole("button", { name: /expand hook event details/i });
+    expect(btn).toBeInTheDocument();
+    expect(btn).toHaveAttribute("aria-expanded", "false");
+  });
+
+  it("toggles aria-expanded on Space key press", async () => {
+    const user = userEvent.setup();
+    render(<SessionHooksPanel sessionId="sess_123" initialData={defaultPayload} />);
+    const btn = screen.getByRole("button", { name: /expand hook event details/i });
+    btn.focus();
+    await user.keyboard(" ");
+    expect(btn).toHaveAttribute("aria-expanded", "true");
+    await user.keyboard(" ");
+    expect(btn).toHaveAttribute("aria-expanded", "false");
+  });
+
+  it("toggles aria-expanded on Enter key press", async () => {
+    const user = userEvent.setup();
+    render(<SessionHooksPanel sessionId="sess_123" initialData={defaultPayload} />);
+    const btn = screen.getByRole("button", { name: /expand hook event details/i });
+    btn.focus();
+    await user.keyboard("{Enter}");
+    expect(btn).toHaveAttribute("aria-expanded", "true");
+  });
+
+  it("toggles aria-expanded on button click", async () => {
+    const user = userEvent.setup();
+    render(<SessionHooksPanel sessionId="sess_123" initialData={defaultPayload} />);
+    const btn = screen.getByRole("button", { name: /expand hook event details/i });
+    await user.click(btn);
+    expect(btn).toHaveAttribute("aria-expanded", "true");
+  });
+});
diff --git a/app/components/session-hooks-panel.tsx b/app/components/session-hooks-panel.tsx
index 1481c34a..890a277a 100644
--- a/app/components/session-hooks-panel.tsx
+++ b/app/components/session-hooks-panel.tsx
@@ -339,11 +339,20 @@ export default function SessionHooksPanel({ sessionId, initialData }: SessionHoo
                       } ${isExpanded ? "bg-muted/20" : ""}`}
                     >
                       <td className="px-4 py-2">
-                        <ChevronDown
-                          className={`h-3.5 w-3.5 text-muted-foreground transition-transform duration-150 ${
-                            isExpanded ? "rotate-0" : "-rotate-90"
-                          }`}
-                        />
+                        <button
+                          type="button"
+                          onClick={(e) => { e.stopPropagation(); toggleRow(i); }}
+                          aria-expanded={isExpanded}
+                          aria-label={`${isExpanded ? "Collapse" : "Expand"} hook event details`}
+                          className="focus:outline-none focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-2 rounded-sm"
+                        >
+                          <ChevronDown
+                            className={`h-3.5 w-3.5 text-muted-foreground transition-transform duration-150 ${
+                              isExpanded ? "rotate-0" : "-rotate-90"
+                            }`}
+                            aria-hidden="true"
+                          />
+                        </button>
                       </td>
                       <td className="px-3 py-2">
                         <DecisionBadge decision={item.decision} />
diff --git a/app/policies/hooks-client.tsx b/app/policies/hooks-client.tsx
index 6cef0b47..eafb642d 100644
--- a/app/policies/hooks-client.tsx
+++ b/app/policies/hooks-client.tsx
@@ -687,11 +687,20 @@ function ActivityTab({
                         } ${isExpanded ? "bg-muted/20" : ""}`}
                       >
                         <td className="px-4 py-2">
-                          <ChevronDown
-                            className={`h-3.5 w-3.5 text-muted-foreground transition-transform duration-150 ${
-                              isExpanded ? "rotate-0" : "-rotate-90"
-                            }`}
-                          />
+                          <button
+                            type="button"
+                            onClick={(e) => { e.stopPropagation(); toggleRow(i); }}
+                            aria-expanded={isExpanded}
+                            aria-label={`${isExpanded ? "Collapse" : "Expand"} hook event details`}
+                            className="focus:outline-none focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-2 rounded-sm"
+                          >
+                            <ChevronDown
+                              className={`h-3.5 w-3.5 text-muted-foreground transition-transform duration-150 ${
+                                isExpanded ? "rotate-0" : "-rotate-90"
+                              }`}
+                              aria-hidden="true"
+                            />
+                          </button>
                         </td>
                         <td
                           className="px-3 py-2 text-muted-foreground whitespace-nowrap"