The road transport industry is worried a plan by police to axe specialist safety officers will mean cowboy truck drivers will go unnoticed.
The Police's Commercial Vehicle Investigation Unit is proposing to lose the country's 26 vehicle safety officers because of a shortfall in funding.
The Road Transport Forum's chief executive, Ken Shirley, said those officers were critical to the safety of roads.
He said it ran the risk of arbitrary and wrong decisions being made by inexperienced police officers.
"If truckers can get away with overloading, breaching the work-time rule, not paying the right RUC (road user charges), that means they are competing unfairly against other truck operators," he said.