MONTPELIER, Vt. — A 22-year veteran of the Vermont State Police resigned Tuesday after alleged discrepancies were discovered in his pays sheets and amid accusations he charged the state for overtime he didn’t work, Gov. Peter Shumlin and other state officials announced.

Last year, former Sgt. James Deeghan of Colchester was paid about $136,000, about $56,000 more than his base pay, although a trooper can typically expect to make about $30,000 in overtime a year, the officials said during a hastily called late afternoon news conference at the governor’s office in Montpelier.

An obviously upset Shumlin said both he and the state were committed to ensuring that Vermont taxpayers aren’t taken advantage of.

“This administration will not tolerate taxpayers being robbed from in any way, shape or form,” Shumlin said.

There are two investigations under way, Shumlin said. One is a criminal investigation into Deeghan’s alleged actions. The other will hire an independent auditor who will look at whether there is a pattern of activity in other areas of the state police.

There is no immediate indication the case goes beyond one person, but the investigation will look into that.

No phone number for Deeghan could immediately be found Tuesday. Officials did not know if Deeghan has a lawyer.

Deeghan, 49, joined the state police in 1990. He had been working out of the Williston barracks. Officials did not know if he had worked elsewhere in Vermont.

The case first came to light last Thursday, when another trooper looked at one of Deeghan’s time sheets for an overtime code. The second trooper then noticed that Deeghan had filed for overtime worked by the trooper seeking the overtime code, Shumlin said.

The second trooper reported the finding to his supervisor, who passed the information up the chain of command. Public Safety Commissioner Keith Flynn learned of it on Monday.

State Police Col. Thomas L’Esperance said Deeghan was suspended without pay on Monday night. He resigned Tuesday morning.

Secretary of Administration Jeb Spaulding said Deeghan’s base pay was about $80,000. Last year Deeghan made about $136,000.

L’Esperance said troopers typically earn about $30,000 a year in overtime.

A supervisor did sign off on Deeghan’s time sheets, but it’s unclear if it was the same person. That is part of the broader investigation, L’Esperance said.

L’Esperance said other troopers felt betrayed by Deeghan’s alleged actions.

“This is a case of a public servant who was entrusted with a job to do,” L’Esperance said. “He betrayed his badge, his core values and across the state this will have a shock wave among state police members that will have a long-lasting effect.”