An Uber driver accused of killing six people during mass shootings in Michigan is competent to understand the murder charges and assist his attorney, a judge said Friday, a key step to putting the criminal case back on track.

A mental exam of Jason Dalton at a state hospital wasn't intended to determine whether the 45-year-old was insane at the time of the Feb. 20 shootings, but rather whether he understands the charges and can assist his defense.

During a very brief hearing, Judge Tiffany Ankley said Dalton is competent.

Dalton is charged with murder and attempted murder. Police said he shot people outside an apartment building, a restaurant and a car dealership in between driving for Uber. Two victims, including a teenager, survived.

Dalton told police after the shootings that a "devil figure" on Uber's app was controlling him, according to documents released by investigators.

Defense attorney Eusebio Solis wants Dalton's statements suppressed, although prosecutor Jeff Getting said he doesn't plan to use them on May 20, the date of a critical hearing to determine if there's enough evidence to send the case to trial.