Union members have the right to union representation during any conversation with a supervisor or manager that could lead to discipline.
These rights have been upheld by the Supreme Court and they are known as Weingarten Rights. For UPS Teamsters, this means that you have the right to Union Representation when management is conducting any kind of investigation, be it into your numbers or an accident.
Make sure that your rights are respected by telling management “If this discussion could in any way lead to me being disciplined, terminated or affect my personal working conditions, I request that a union steward, business agent or union officer be present at this meeting."
Without representation, I choose not to answer any questions.” The remain silent. If your proceed your rights will be waived.