Selectmen recently decided to delay granting renewal of a permit to operate a 175-space commuter rail parking lot after the owners refused to pay a percentage of a police traffic detail. Father and son businessmen Karl D. and Bill Clemmey, who own the lot off of Foundry Street, owe the town about $6,200 for the police detail for the past year, but have told the town they will not pay it, according to Town Manager William R. Ross. “We had a discussion a year ago,” Ross said in an interview, that led to an agreement to pay reduced permit fees and set the fee for all the owners — including the MBTA and the town — based on the percentage of parking spots each one owns in the area. “Apparently it wasn’t good enough,” Ross said. Bill Clemmey said in an interview that according to research done by his attorney, the fee is illegal. He cited a lawsuit involving Emerson College that found that fees of this type have to be found to be caused by those being charged. The town hasn’t met any of the necessary three criteria required to show that traffic backup in the area during rush hours is the result of the commuters leaving the parking lot, and is not just the result of already heavy traffic on Route 106 (Chauncy Street), he said. “The traffic is a public safety issue and the town should be paying for public safety issues,” Clemmey said.