LAFAYETTE, IND. A charter bus rules violation complaint filed against this city's public transit agency apparently has grown into a federal criminal investigation.

Agents from the U.S. Department of Transportation's Office of Inspector General are looking into the possibility the Greater Lafayette Public Transportation Corp., which operates under the name CityBus, may have falsified documents so it would not have to first offer some charter business to private motorcoach operators.

Federal charter bus rules limit the type of charters that tax-funded public transit agencies are allowed to do without first giving private carriers the opportunity to bid on the work.

The Federal Transit Administration began looking into CityBus several months ago in response to a complaint filed by Imperial Travel Service of Lafayette, which contended the transit agency was conducting charter business that should have been offered to private companies.

The investigation is winding down and a ruling is expected to be announced within the next few weeks, according to the FTA regional office in Chicago.

While Imperial President James Galloway says in his complaint that CityBus has frequently violated federal charter bus rules, he singled out its charter shuttle service for the annual Feast of the Hunter's Moon Festival, which draws thousands to the city.

He said CityBus attempted to pass off its shuttle service to the event as simply an extension of its regular daily bus route, which could make it legal for the agency to provide the service. However, Galloway says the route CityBus said it was extending ran only on weekdays and the event was held on the weekend.

Inside sources also have told Galloway that the route was extensively modified and "decoy buses" were used to try to mask the illegal operation.

"We never even had a chance to bid on the festival," said Galloway. "We should not have to compete with the government because they have very deep pockets."

The FTA began its probe as a routine charter bus rules violation investigation, but brought in criminal investigators from the Inspector Generals Office after it received information from Galloway that CityBus may have altered some applications for charter service to show the customers required buses with wheelchair lifts, when, in fact, they had not done so.

Such a request would boost the opportunity for CityBus to provide the service because most of its fleet is equipped with wheelchair lifts and special seating areas.

Madeline Chulumovich, a spokeswoman for the Inspector General's Office in Washington D.C., declined to comment, saying the federal agency never comments on what it may or may not be investigating.

Also, City Bus Manager Martin Sennett would not comment on the investigation, according to agency spokesman John Mitzinger.