A government watchdog group found that 18 Long Island retirees are collecting full public pensions while back on the job for the state.

The practice known as "double dipping" is legal, but a special waiver is needed if the salary of the new job exceeds a certain limit.

Empire Center for Public Policy, Inc. says those waivers could end up being costly for taxpayers. It also says the public has no say in the matter.

One of the people receiving a waiver is Eric Kopp. He retired two years ago and gets a pension of $84,000 a year. He then returned to become chief-of-staff for Suffolk County Executive Steve Bellone at a salary of $55,000.

The Bellone administration says taxpayers are getting their money's worth out of Kopp. They say they asked the state for a waiver in order to entice a very experienced county worker out of retirement.

Many of those who received waivers are retired police officers who work as investigators for the district attorney or local police departments.