In the event of malicious interference, unidentified transmissions, rude comments, etc., do not acknowledge it! If a conversation is in progress, simply ignore it and continue as if nothing happened. If the interference escalates to the point where it is impossible to carry on the conversation, simply end the communication and sign off as you normally would. Do not acknowledge or respond to the interference or unidentified stations in any manner. Do not discuss instances of interference on the repeater on which it occurred, nor on any another frequency.

Considering that all stations must legally identify, if you hear unidentified transmissions, or suspect that a station is not properly licensed, or is using a fake callsign ("bootlegging"), do not converse with them unless and until you have a way to verify their identity and authorization. In addition to unlicensed operation itself being illegal, communicating with an unlicensed station is also a violation.