GRAND RAPIDS (WWJ/AP) – A jury was selected Monday in the trial of a 13-year-old boy charged with fatally stabbing a 9-year-old boy at a western Michigan playground.

Twelve jurors and two alternates were chosen. Opening statements and evidence will be offered Tuesday in Kent County court in Grand Rapids.

READ MORE: Michigan Matters: The Political Road Ahead

Jamarion Lawhorn , who was 12 at the time, is charged with murder in the death of Michael Connor Verkerke a year ago in Kentwood, near Grand Rapids. He is designated as an adult in the juvenile court system, which means he would be sentenced as a juvenile if convicted and then resentenced as an adult at age 21.

Lawhorn’s mental health could be an issue at trial, although he was found competent to understand the charges against him and assist his lawyer.

There doesn’t seem to be a dispute about what happened. Verkerke was playing with his 7-year-old brother and his 9-year-old best friend on Aug. 4, 2014, when Lawhorn pulled a knife and stabbed Verkerke in the back.

[9-Year-Old Stabbed At Playground Tells Brother ‘I’ll Always Love You’ In Dying Breath]

READ MORE: 'My Name Is Sara' Film On Holocaust Survivor Premieres In Metro Detroit

Verkerke ran to his home and collapsed, bleeding on the porch, while Lawhorn went to a neighbor’s home nearby to call police and turn himself in. Verkerke died a short time later at a hospital.

Lawhorn has been described as behaving “very calmly” after the stabbing. Witnesses said the boy mentioned that he was upset because nobody loved him, and that he had taken multiple pills earlier in the day. After the stabbing, a neighbor told police that the boy said, “I want to die. I don’t want to be on this earth anymore.”

According to a court filing, Lawhorn told investigators he stabbed Verkerke because he wanted to go to jail, that he is “bad and always does stupid things,” and that he thought he’d be killed “for doing something like this.” The boys didn’t know each other.

Lawhorn’s parents have been charged with child abuse, which authorities believe may have contributed to the boy’s mental state, and, in turn, the stabbing. Records showed that he had been living in a volatile home that was described as “deplorable” by child welfare workers.

WWJ is identifying Lawhorn, who turned 12 in March, because he is charged as an adult.

MORE NEWS: Dearborn Homecoming Festival Kicks Off This Weekend

TM and © Copyright 2015 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2015 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.