(Reuters) - A former Uber driver who pleaded guilty to opening fire in a string of parking lots across Kalamazoo, Michigan, killing six people and wounding two others, was sentenced on Tuesday to life in prison without the possibility of parole.

FILE PHOTO: Jason Dalton, now 48, is shown in this booking photo provided by the Kalamazoo County Sheriff's Office in Kalamazoo, Michigan, U.S. Feb. 21, 2016. Kalamazoo County Sheriff's Office/Handout via Reuters/File Photo/File Photo

Jason Dalton, 48, showed no emotion as he was ordered to spend the rest of his life behind bars by Kalamazoo County Circuit Court Judge Alexander Lipsey.

“Early in my tenure as judge, I was given some sage wisdom: Our prisons are not designed to be for those folks we’re mad at. They are designed for those folks we are afraid of. And you clearly fall into that category,” Lipsey said in imposing the sentence.

Prosecutors said Dalton opened fire on Feb. 20, 2016, apparently at random, in parking lots outside an apartment building, a car dealership and a Cracker Barrel restaurant in Kalamazoo, about 150 miles (240 km) west of Detroit.

He was taken into custody and charged with 16 counts, including six counts of murder and two counts of attempted murder.

The carnage in Kalamazoo, a city of about 75,000 people, was another in a series of mass shootings that has touched off a national debate over gun control.

The attack also prompted renewed interest in how Uber vets drivers, who use their personal vehicles to ferry customers at prices generally below those of established taxi companies. Uber said at the time that Dalton had passed background checks.

Defense attorneys initially sought to mount an insanity defense on his behalf. But following a psychiatric evaluation, a judge ruled that Dalton was mentally competent to stand trial.

In March 2016, Dalton filed a $10 million federal civil rights lawsuit against the ride-sharing company after telling investigators that Uber’s app had the ability to “take over” his body and compel him to kill.

He told police that when he pressed a button on his phone screen, the horned-cow head of a devil would appear and give him an assignment that he said would “literally take over” his body, local television station WZZM reported.

Dalton abruptly pleaded guilty to all of the charges against him, against the advice of his attorneys, on Jan. 7 while a jury was being selected for his upcoming trial.