A former Morrisville police corporal was convicted Thursday of official oppression, terroristic threats, harassment, and unlawful use of a computer after a judge found that he used a police database to obtain personal information on a couple he later threatened.

Michael Pitcher, 43, used his access to a confidential database to look up vehicle registration information on a Porsche to identify a man he believed had driven the car too slowly in front of him as he was on his way to work. He later called the driver at home and threatened him, using an application on his cellphone to hide his number.

In finding Pitcher guilty of the crimes on Thursday morning, Bucks County Judge Brian T. McGuffin accused the officer of lying on the stand during his trial when he said he called the man as part of an official investigation.

“You called them to hassle them,” McGuffin told Pitcher. “To get back at them for some perceived affront against your authority.”

Pitcher testified that he made the call because the driver of the Porsche was operating it recklessly, and issued a warning that he might hurt himself or someone else.

But the car’s owner, Jerry Shanks, told the judge he picked up the phone to hear the “very threatening, aggressive voice” of someone who knew both his name and his address, and said he should buy cameras for his home because the caller was going to destroy the vehicle.

Shanks contacted police in Lower Makefield, who traced the call to Pitcher, investigators said. They later determined that Pitcher had waited until he was alone in the police station to make the phone call, and deleted evidence of the call from his phone, as well as records of the research he had done on his computer into using the spoofing application.

And despite telling McGuffin the call was part of an official investigation into Shanks’ reckless driving, Pitcher made no record of it in his daily logbook.

In closing arguments Wednesday evening, Pitcher’s attorney, Louis Busico, urged McGuffin to acquit Pitcher, pointing to the friends, neighbors, and coworkers who testified as character witnesses on his behalf.

“In order for the commonwealth’s case to make sense, you’d have to believe that as a police officer who reached the rank of corporal, he picked out Mr. and Mrs. Shanks for no reason other than to oppress them,” Busico said. “That doesn’t make a modicum of sense.”

Deputy Attorney General Brian Zarallo disputed the defense theory, saying the elements of the prosecution’s case against Pitcher fit together as tightly “as a Swiss watch.”

“He tried to sell this as something credible and legitimate, but the evidence shows this was as far away from credible and legitimate as possible,” Zarallo said of Pitcher. “The idea was to scare them, and he did that, badly. What he didn’t count on was that they wouldn’t take it lying down, and would call the police to investigate.”

After finding Pitcher guilty, McGuffin ordered him to be placed on electronic monitoring until his sentencing, tentatively scheduled for December.