A second defendant has agreed to serve a long prison term for his role in the fatal shooting of a man outside his St. Paul home who was trying to foil the theft of items from his wife's vehicle.

Ta Mla, 18, agreed Thursday in Ramsey County District Court to plead guilty to second-degree unintentional murder in connection with the killing of 44-year-old Michael Brasel on May 6 in the quiet and tight-knit St. Anthony Park neighborhood.

The plea agreement between the prosecution and the defense calls for Mla to receive a sentence of 15 years. With credit for time in jail, Mla is expected to serve roughly the first 9⅔ years in prison and the balance on supervised release.

In the meantime, Mla remains jailed ahead of sentencing scheduled for Dec. 14.

Mla's accomplice, 18-year-old Kle Swee, was the shooter who killed Brasel, a father of two boys. Brasel was also a youth hockey coach.

Swee, who was 17 at the time of the crime, was sentenced in adult court on Oct. 4 to a 25-year term. He's serving the first 16⅔ years in prison followed by the remainder on supervised release.

According to the criminal complaints:

Brasel's wife, Hilary Brasel, said her husband saw someone rummaging through her car parked in the 2300 block of Chilcombe Avenue. Brasel's son told investigators he heard his dad yell, "What are you doing?" before gunshots rang out.

" 'My bad, bro,' " Mla told police was Swee's response immediately afterward, the charges read. " 'I didn't mean to.' "

Hilary Brasel went to her wounded husband and started chest compressions and called for help as onlookers called 911. Brasel's wife said someone apparently had rifled through the car and placed items from the center console on the driver's seat.

Investigators reviewed neighbors' camera footage and saw the suspected vehicle leaving the crime scene. Officers pieced together a call to Lauderdale police earlier that day about a similar vehicle there that lost its bumper while swerving to avoid a stopped car. Officers recovered the bumper with a Minnesota license plate that was registered to a 2009 Honda coupe.

Swee was arrested with a Honda key in his pocket and declined to speak to law enforcement. Officers found the Honda in Swee's garage with no front bumper.

Investigators put Mla, who has a criminal history involving guns as a juvenile, at the scene by testing for DNA on a small camouflage bag recovered by police from the SUV's front seat. Mla's DNA was found on the bag. He was arrested in St. Paul on June 6 during a traffic stop.