My understanding, in the U.K., is that if somebody committed a serious crime, they would immediately be terminated from the program. The part of the memorandum of understanding that is set up between witnesses and the police force that is protecting them would make it quite clear that any form of criminal activity would result in a person ceasing to have protection from that police force. That would be the case in the U.K.
On May 31st, 2007. See this statement in context.