New details have emerged in the case of the Yale police officer arrested on charges of workers’ compensation fraud.

The arrest warrant affidavit for 58-year-old Richard Nicholson — sidelined since September 1996 because of a motorcycle injury he suffered on the job — alleges that he worked as a traffic controller in Montville while simultaneously collecting total disability benefits from the University. Nicholson allegedly concealed this job from the Yale Police Department and consequently violated his contract.

The Office of the Chief State’s Attorney estimated that Nicholson, an Oakdale resident, collected in excess of $20,000 while on disability leave. He faces a maximum of 20 years in prison if convicted.

But Nicholson’s attorney, Richard L. Jacobs, said his client did not intend to defraud the department. He said Nicholson did not commit any intentionally illegal act because he voluntarily disclosed his Montville job in a May 2001 deposition.

“Mr. Nicholson is an honest man and will be vindicated,” Jacobs said.

Repeated phone calls to Nicholson’s home were not returned.

Kevin Calderwood, an inspector in the state’s Workers’ Compensation Fraud Unit, wrote in his affidavit that Nicholson’s culpability stemmed from his failure to inform anyone of his Montville job — including the Yale Workers’ Compensation Office, the Yale Police and his physician — before he was deposed regarding the fraud charges.

Yale Police Chief James Perrotti declined to comment on the case, saying the department does not speak publicly on personnel matters.

This is not the first time Nicholson has collected workers’ compensation: He was out on disability in 1992, 1995, and again in 1999 through 2000, according to the affidavit.

The affidavit cites Yale attorney John Letizia as saying that this past experience should have given Nicholson thorough knowledge of his responsibilities while on leave. Letizia also said Nicholson was given ample advice and warning to comply with the requisite disability procedures.

Neither Letizia nor Neil Ambrose, the Yale attorney who originally deposed Nicholson, was available for comment on Thursday.

The traffic controller job Nicholson started in January 2001 is not a desk job. It has a number of physical demands, such as the ability to stand and raise and move one’s hands for prolonged periods of time, according to the affidavit.

In addition, a physician’s letter confirming an applicant’s physical fitness is sometimes required as part of the application. Calderwood wrote that Nicholson — whose elbows required surgery after the injury — told Lt. Lenny Bunnell of the Montville Police that he had a doctor’s clearance to perform traffic duty.

According to the affidavit, Joseph Slade, Nicholson’s treating physician, did not release him to regular duty until May 2001. Slade could not be reached for comment Wednesday.

The affidavit states that Bunnell — a 25-year friend of Nicholson’s who worked with him on the Montville force — did not know at the time that Nicholson lacked medical permission to perform his duties as a traffic controller. Bunnell declined to comment further when contacted Wednesday, deferring all questions to the Montville mayor’s office. Repeated phone calls to the mayor’s office were not returned.

Nicholson is scheduled to be arraigned on April 5 in New Haven Superior Court.