diff --git a/apps/backend/app.ts b/apps/backend/app.ts
index e6abbba2..c2b3ddc2 100644
--- a/apps/backend/app.ts
+++ b/apps/backend/app.ts
@@ -12,7 +12,6 @@ import { library_route } from './routes/library.route.js';
 import { schedule_route } from './routes/schedule.route.js';
 import { events_route } from './routes/events.route.js';
 import { request_line_route } from './routes/requestLine.route.js';
-import { showMemberMiddleware } from './middleware/checkShowMember.js';
 import { activeShow } from './middleware/checkActiveShow.js';
 import errorHandler from './middleware/errorHandler.js';
 import { requestIdMiddleware } from './middleware/requestId.js';
diff --git a/apps/backend/controllers/flowsheet.controller.ts b/apps/backend/controllers/flowsheet.controller.ts
index 9ac09f27..7b892fcd 100644
--- a/apps/backend/controllers/flowsheet.controller.ts
+++ b/apps/backend/controllers/flowsheet.controller.ts
@@ -354,11 +354,8 @@ export const leaveShow: RequestHandler<object, unknown, { dj_id: string }> = asy
     res.status(404).json({ message: 'Bad Request: No active show session found.' });
   } else {
     try {
-      // Catch case where DJ is not in show, but attempting to hit this endpoint
-      const show_djs = await flowsheet_service.getDJsInCurrentShow();
-      if (!show_djs.map((dj) => dj.id).includes(req.body.dj_id)) {
-        res.status(400).json({ message: 'Bad Request: DJ not in current show' });
-      } else if (req.body.dj_id === currentShow.primary_dj_id) {
+      // Show membership is verified by showMemberMiddleware on the route
+      if (req.body.dj_id === currentShow.primary_dj_id) {
         const finalizedShow: Show = await flowsheet_service.endShow(currentShow);
         res.status(200).json(finalizedShow);
       } else {
diff --git a/apps/backend/middleware/checkShowMember.ts b/apps/backend/middleware/checkShowMember.ts
index 8d07269f..703d885e 100644
--- a/apps/backend/middleware/checkShowMember.ts
+++ b/apps/backend/middleware/checkShowMember.ts
@@ -2,16 +2,21 @@ import { RequestHandler } from 'express';
 import { getDJsInCurrentShow } from '../services/flowsheet.service.js';
 
 export const showMemberMiddleware: RequestHandler = async (req, res, next) => {
-  const show_djs = await getDJsInCurrentShow();
-  // Get user ID from JWT - check both req.auth (from better-auth middleware) and res.locals (legacy)
-  const user_id = req.auth?.id || req.auth?.sub || res.locals.decodedJWT?.id || res.locals.decodedJWT?.userId;
-  const dj_in_show = show_djs.filter((dj) => {
-    return dj.id === user_id;
-  }).length;
+  if (process.env.AUTH_BYPASS === 'true') {
+    return next();
+  }
+
+  try {
+    const show_djs = await getDJsInCurrentShow();
+    const user_id = req.auth?.id || req.auth?.sub || res.locals.decodedJWT?.id || res.locals.decodedJWT?.userId;
+    const dj_in_show = show_djs.some((dj) => dj.id === user_id);
 
-  if (dj_in_show > 0) {
-    next();
-  } else {
-    res.status(400).json({ message: 'Bad Request: DJ not a member of show' });
+    if (dj_in_show) {
+      next();
+    } else {
+      res.status(400).json({ message: 'Bad Request: DJ not a member of show' });
+    }
+  } catch {
+    res.status(500).json({ message: 'Internal server error checking show membership' });
   }
 };
diff --git a/apps/backend/routes/flowsheet.route.ts b/apps/backend/routes/flowsheet.route.ts
index 38385dc5..bcf8c7f3 100644
--- a/apps/backend/routes/flowsheet.route.ts
+++ b/apps/backend/routes/flowsheet.route.ts
@@ -3,6 +3,7 @@ import { Router } from 'express';
 import * as flowsheetController from '../controllers/flowsheet.controller';
 import { flowsheetMirror } from '../middleware/legacy/flowsheet.mirror';
 import { conditionalGet } from '../middleware/conditionalGet';
+import { showMemberMiddleware } from '../middleware/checkShowMember';
 
 export const flowsheet_route = Router();
 
@@ -11,6 +12,7 @@ flowsheet_route.get('/', conditionalGet, flowsheetMirror.getEntries, flowsheetCo
 flowsheet_route.post(
   '/',
   requirePermissions({ flowsheet: ['write'] }),
+  showMemberMiddleware,
   flowsheetMirror.addEntry,
   flowsheetController.addEntry
 );
@@ -18,6 +20,7 @@ flowsheet_route.post(
 flowsheet_route.patch(
   '/',
   requirePermissions({ flowsheet: ['write'] }),
+  showMemberMiddleware,
   flowsheetMirror.updateEntry,
   flowsheetController.updateEntry
 );
@@ -25,6 +28,7 @@ flowsheet_route.patch(
 flowsheet_route.delete(
   '/',
   requirePermissions({ flowsheet: ['write'] }),
+  showMemberMiddleware,
   flowsheetMirror.deleteEntry,
   flowsheetController.deleteEntry
 );
@@ -32,6 +36,7 @@ flowsheet_route.delete(
 flowsheet_route.patch(
   '/play-order',
   requirePermissions({ flowsheet: ['write'] }),
+  showMemberMiddleware,
   /*flowsheetMirror.changeOrder,*/
   flowsheetController.changeOrder
 );
@@ -48,6 +53,7 @@ flowsheet_route.post(
 flowsheet_route.post(
   '/end',
   requirePermissions({ flowsheet: ['write'] }),
+  showMemberMiddleware,
   flowsheetMirror.endShow,
   flowsheetController.leaveShow
 );
diff --git a/apps/backend/services/flowsheet.service.ts b/apps/backend/services/flowsheet.service.ts
index 3dafb34d..e25293f9 100644
--- a/apps/backend/services/flowsheet.service.ts
+++ b/apps/backend/services/flowsheet.service.ts
@@ -1,4 +1,5 @@
 import { sql, desc, eq, and, lte, gte, inArray } from 'drizzle-orm';
+import WxycError from '../utils/error.js';
 import {
   db,
   FSEntry,
@@ -419,7 +420,7 @@ export const leaveShow = async (dj_id: string, currentShow: Show): Promise<ShowD
 
   // In case gaurds further up the line of logic fail
   if (update_result === undefined) {
-    throw new Error('DJ not in show');
+    throw new WxycError('Bad Request: DJ not a member of show', 400);
   }
 
   // -- Add DJ Left to Flowsheet --
diff --git a/tests/unit/middleware/checkShowMember.test.ts b/tests/unit/middleware/checkShowMember.test.ts
new file mode 100644
index 00000000..206dc01b
--- /dev/null
+++ b/tests/unit/middleware/checkShowMember.test.ts
@@ -0,0 +1,80 @@
+import { jest } from '@jest/globals';
+import type { Request, Response, NextFunction } from 'express';
+
+const mockGetDJsInCurrentShow = jest.fn<() => Promise<{ id: string }[]>>();
+
+jest.mock('../../../apps/backend/services/flowsheet.service', () => ({
+  getDJsInCurrentShow: mockGetDJsInCurrentShow,
+}));
+
+import { showMemberMiddleware } from '../../../apps/backend/middleware/checkShowMember';
+
+function createMockReqResNext(userId: string) {
+  const req = {
+    auth: { id: userId },
+  } as unknown as Request;
+
+  const statusMock = jest.fn().mockReturnThis();
+  const jsonMock = jest.fn().mockReturnThis();
+  const res = {
+    status: statusMock,
+    json: jsonMock,
+    locals: {},
+  } as unknown as Response;
+
+  const next = jest.fn() as unknown as NextFunction;
+
+  return { req, res, next, statusMock, jsonMock };
+}
+
+describe('showMemberMiddleware', () => {
+  it('rejects a DJ who is not in the current show', async () => {
+    mockGetDJsInCurrentShow.mockResolvedValue([{ id: 'dj-alice' }, { id: 'dj-bob' }]);
+
+    const { req, res, next, statusMock, jsonMock } = createMockReqResNext('dj-charlie');
+
+    await showMemberMiddleware(req, res, next);
+
+    expect(statusMock).toHaveBeenCalledWith(400);
+    expect(jsonMock).toHaveBeenCalledWith({
+      message: 'Bad Request: DJ not a member of show',
+    });
+    expect(next).not.toHaveBeenCalled();
+  });
+
+  it('allows a DJ who is in the current show', async () => {
+    mockGetDJsInCurrentShow.mockResolvedValue([{ id: 'dj-alice' }, { id: 'dj-bob' }]);
+
+    const { req, res, next, statusMock } = createMockReqResNext('dj-alice');
+
+    await showMemberMiddleware(req, res, next);
+
+    expect(next).toHaveBeenCalled();
+    expect(statusMock).not.toHaveBeenCalled();
+  });
+
+  it('rejects when there are no DJs in the current show', async () => {
+    mockGetDJsInCurrentShow.mockResolvedValue([]);
+
+    const { req, res, next, statusMock } = createMockReqResNext('dj-alice');
+
+    await showMemberMiddleware(req, res, next);
+
+    expect(statusMock).toHaveBeenCalledWith(400);
+    expect(next).not.toHaveBeenCalled();
+  });
+
+  it('returns 500 when getDJsInCurrentShow throws', async () => {
+    mockGetDJsInCurrentShow.mockRejectedValue(new Error('DB connection lost'));
+
+    const { req, res, next, statusMock, jsonMock } = createMockReqResNext('dj-alice');
+
+    await showMemberMiddleware(req, res, next);
+
+    expect(statusMock).toHaveBeenCalledWith(500);
+    expect(jsonMock).toHaveBeenCalledWith({
+      message: 'Internal server error checking show membership',
+    });
+    expect(next).not.toHaveBeenCalled();
+  });
+});