This means you have the right to union representation when supervisors question you about mistakes or alleged wrongdoing.
Weingarten rights are a big protection against management intimidation.
You can invoke your Weingarten rights and ask for a union shop steward to join in on your behalf. Stewards can take you aside for a private pre-interview conference before questioning begins. They serve as a witness to prevent supervisors from lying about the conversation. They can interrupt to object to intimidating tactics. They can speak on your behalf and warn you against losing your temper.