MONTPELIER, Vt. -- The state Supreme Court on Friday overturned the murder conviction of a man who said he was acting in self-defense when he shot another man during a confrontation in a park in 2008.

The court’s decision ordered a new trial for Kyle Bolaski for the shooting of Vincent Tamburello after Tamburello chased Bolaski while wielding a splitting maul, an axe-like tool used to split wood.

In its decision, the court determined the judge had given improper instructions to the jury and excluded evidence of the victim’s mental health in the months before the shooting.

Bolaski was convicted of the shooting in 2011 and was sentenced to 25 years to life in prison. He’s incarcerated in Kentucky.

Defender General Matthew Valerio, whose office represented Bolaski on appeal, said it was possible Bolaski would be brought back to Vermont and his office would begin discussions with prosecutors about whether to go forward with another trial.

Bolaski and Tamburello were at the Chester ball field on Aug. 17, 2008, when Tamburello got out of his vehicle holding a stun gun and "sparking it," the court’s decision said. An unarmed group that included Bolaski approached Tamburello’s car. Tamburello tossed the stun gun into the car and pulled out the splitting maul and chased Bolaski to Bolaski’s truck.

Bolaski got a rifle from his truck and "under highly disputed circumstances" shot Tamburello twice, once in the leg and once in the buttocks, the court’s decision said. Tamburello bled to death from the second shot.

Bolaski acknowledged shooting Tamburello but said it was in self-defense.

A toxicology report found a number of legal and illegal drugs in Tamburello’s blood and urine.

The prosecution argued against self-defense and suggested that the testimony of the witnesses whose accounts were more consistent with the defendant’s as to the victim’s last actions was biased and inconsistent.