Under the National Labor Relations Act

If you reasonably believe that answering a question may lead to discharge, discipline, demotion, or other adverse consequence to your job status or working conditions, you should request a shop steward before answering it.

You have the legal right to union representation when being asked potentially disciplinary questions. These are called your Weingarten rights, named after the supreme court case that upheld them in 1975.

You have the right to stop the meeting until union representation arrives. Simply say "I will not answer further questions without union representation." and contact your union rep or shop steward.

Your shop steward will provide active assistance in the interview, keep an independent record of the meeting, and enforce your rights. If management refuses to allow a shop steward, or states that an interview is non-disciplinary, please inform a shop steward or your union rep.

This only applies to union-represented stores.

You have the right to discuss union matters at work, including talking about contract negotiations, wages, direct action, union meetings etc. wherever you could ordinarily have a personal conversation, including on the clock. If a customer asks you about union business, you have the right to talk to them about it.

These rights apply at all stores, union or not.

You have the right to join, form, or assist a union. It is illegal for management to interrogate you about union activities, including signing a union card, coming to union meetings, presenting group grievances to management, or participating in your store's organizing committee. It is illegal for management to threaten, interrogate, or surveil you in connection with protected union activity. It is illegal for management to take your union support into consideration for promotion or transfer decisions.

These rights apply at all stores, union or not.