PORTAGE, Mich. (WOOD) — A judge has ordered an inquiry into whether a Portage man accused of killing his parents is competent to stand trial.

The competency exam for Nicholas Johnson, 27, was ordered Tuesday after a motion from his defense. A status review was scheduled for May 11.

The competency exam will not determine sanity at the time of the crime, but instead whether Johnson understands the case against him and can help in his own defense, as he is entitled.

Johnson was charged with murder and weapons charges after the bodies of his parents, Gary and Laura Johnson, were found buried in Gourdneck State Game Area in Portage, only a few miles from their home.

The murder is believed to have happened Feb. 3. Authorities went to the Johnson’s house Feb. 9 after Gary Johnson’s employer called them, worried that he had not logged in for work in a few days. Court documents show responding officers found blood in the home and in Gary Johnson’s car in the garage, along with a 9 mm shell casing.

Investigators pinged Laura Johnson’s cellphone, which led them to an apartment complex where they found her car, also bloody, and her son. Nick Johnson had a 9 mm handgun.

They followed GPS data from Laura Johnson’s car to Gourdneck State Game Area, where they found evidence of digging. The next day, authorities started digging themselves and recovered the bodies. Both had been shot in the head with a 9 mm.

An undated courtesy photo of Gary and Laura Johnson.

During arraignment, Nick Johnson’s attorney said he had a problem of mental health issues. The attorney also said Johnson maintains his innocence.

He is also considered a person of interest in the disappearance of Bonifacio Pena, 17, originally of Gobles. Police say their investigation found Johnson was the last person seen with Pena before he vanished in May 2018.