SOUTHBURY, Conn. (WTNH) — A Connecticut State Police Sergeant is under investigation after he allegedly crashed his state vehicle into another car.

The incident happened on Sept. 25 on Route 188 and Airport Access Road in Southbury.

Reports state Sergeant John McDonald was leaving a retirement party for a colleague at Black Hog Brewing, in Oxford, when he ran a stop sign and crashed into a Nissan Altima, causing both cars to go off the road and into the woods.

McDonald and two women — a mother and daughter in the Altima — were taken to the hospital with injuries.

State Police are working to determine if he was under the influence at the time of the crash.

Records indicate that State Police could not give him a blood alcohol test because he was taken to the hospital. Hospital staff would have administered one, except McDonald refused treatment and left.

Investigators said they’ve issued warrants to obtain the hospital’s video surveillance footage.

Troopers are also looking at body camera footage of the scene, video from the brewery, and the ambulance.

“That body cam footage has been secured, and it will be part of the investigation,” said Brian Foley, Connecticut Department of Emergency Services and Public Protection. “And make no mistake about it, investigators will also go to the location of the party, that business there and try to retrieve anything they can get.”

Investigators will also be looking at the actions of troopers at the party, as well as the hospital to ensure they were following protocol.

According to State Police’s vehicle policy, “no employee shall operate a state motor vehicle while under the influence of alcohol or drugs.”

Employees are also required to “maintain a zero percent ratio of alcohol or drugs in their blood while operating a state vehicle…”

So far, no charges have been filed, and the sergeant remains on duty.

However, the breweries, State Police, and the state of Connecticut are being sued as a result of the incident.

As of Oct. 23, the suit states that McDonald was drinking at the retirement party and that he was drunk when he drove away, failed to stop at a stop sign, and crashed into the Altima containing the mother and daughter.