HARTFORD, Conn. — The morning after pulling a wounded fellow police officer to safety at an active shooting scene, state police Master Sgt. Patrick Torneo was found in his cruiser on the side of a road by local officers and taken to the police station in April 2013.

If anything was wrong with Torneo, it isn’t clear. No charges were filed. Middletown police treated it as a “medical issue,” according to court documents.

What is clear is that the next 15 months for Torneo were a rollercoaster ride during which he was promoted to lieutenant and given a bravery award, then suspended and demoted back to master sergeant for an alleged cover-up of unproved accusations that he had driven drunk in the Middletown incident, according to a lawsuit he filed in federal court against state police officials this month.

Torneo, a 16-year state police veteran, accuses top state police officials of improperly demoting him, conducting a biased internal affairs investigation and violating his constitutional due process rights. He’s seeking reinstatement to lieutenant and an undisclosed amount of damages and compensation.

Torneo’s lawyer, Lewis Chimes, declined to comment and said Torneo also would not be speaking about the case.

Chimes wrote in the lawsuit that the internal affairs investigation against Torneo was “truly outrageous.”

State police referred questions to the state attorney general’s office, where a spokeswoman declined to comment.

The defendants include internal affairs investigators, a former state police commanding officer and Dora Schriro, commissioner of the Department of Emergency Services and Public Protection, which oversees state police.

Middletown police said they cannot find any records involving the 2013 encounter with Torneo.

Torneo has been in the news in connection with an unrelated case. He is one of three state troopers accused in a lawsuit of retaliating against a protester at a sobriety checkpoint in West Hartford in 2015 by arresting him on bogus criminal charges. An internal affairs investigation cleared the three troopers of wrongdoing, and they deny the allegations.

In April 2013, Torneo pulled injured state police Detective Scott Wisner from his cruiser in the middle of a shooting involving two robbery suspects in Westbrook. Wisner was shot by one of the suspects after their cars crashed during a chase. Wisner returned fire and wounded the two men. One of the suspects, Jonathan Alvarado, later died, while Wisner and the other suspect survived.

Torneo’s lawsuit gives the following account of what happened next.

Torneo and other state police officers visited Wisner at his home later on the night of the shootout. The next morning, Torneo was found in his cruiser on the side of a road in Middletown by city police. Additional details were not included in the lawsuit. Torneo was later diagnosed and treated for post-traumatic stress disorder connected to the rescue of Wisner.

Torneo was promoted to lieutenant in September 2013 and three months later was awarded a medal for bravery for rescuing Wisner.

State police in 2014 received two anonymous complaints accusing state police officials of covering up the fact that Torneo had driven drunk in the hours after the shootout. An internal affairs investigation was launched, resulting in the demotion and a five-day suspension.

Torneo’s labor union filed a grievance over the discipline. An arbitrator later ruled that state police failed to prove the misconduct and overturned the suspension, but said he lacked authority to rule on the demotion. Torneo then sued state police.

The lawsuit also alleges that Sgt. Andrew Matthews, president of the Connecticut State Police Union, improperly influenced Schriro, the agency commissioner, to remove Torneo as commanding officer of Troop F in Westbrook, which played a role in investigators opening the internal affairs probe against Torneo.

The lawsuit alleges the anonymous complaints and Matthews’ “attacks” on Torneo were motivated by Matthews’ efforts to “pursue the agenda” of female troopers. There had been several sexual discrimination complaints at Troop F at the time. Torneo was not accused of discrimination, but was commanding officer of the troop, the lawsuit says.

The union issued a statement denying any wrongdoing and said it made no attempt to get Torneo demoted.