A law expert says police should not be leading the removal of "court-siders" at the Cricket World Cup, as the practice is a contractual breach, but not illegal.
Court-siding is when people at matches relay information during games to others outside the venue, taking advantage of broadcasting time delays, to influence betting.
On Saturday, police said "several" people caught court-siding were interviewed and removed from Christchurch's Hagley Oval during a game.
But because the act was not illegal, AUT University senior law lecturer Craig Dickson questioned why police were involved.
He said although court-siding was a breach of the terms and conditions of ICC Cricket World Cup tickets, it was not breaking New Zealand laws.
"I'm not sure whether police should have a front foot role in this. They really shouldn't be the first line of enforcement for what is actually a civil, contractual breach."
Mr Dickson said the terms and conditions of the ticket clearly forbade court-siding, but it was not clear where police fitted into the situation, as the ICC had engaged their own security staff for the tournament.
He said if security guards had asked court-siders to leave and they refused, they would be trespassing, but this didn't appear to have been the case.
He said if the court-siders had been taken for questioning by police, it raised the question of what provision they were being questioned under, and what law had been broken.
On Saturday Superintendent Sandy Manderson, the officer in charge of the police's World Cup operation, said police had "several" officers - including plain-clothed police - in and around the grounds looking for court-siders.
A police spokesman said it was their role in the tournament to ensure safety and security, to ensure it was a success and to assist security and the partner agencies to the best of their ability.
"Part of that mandate is to ensure the terms and conditions of tickets are maintained. Court-siding fits into that in the same way that someone who might be intoxicated on a bank drinking fits into that."