The man accused of randomly killing a Chesco woman showed ‘frantic behavior’ during a police interaction earlier that day

The man charged with shooting and killing a woman who was driving her car in Chester County on Saturday had a run-in with police earlier that day but was allowed to leave the scene with his gun, according to a criminal complaint.

Steve Jahn, 44, was arrested and charged with first-degree murder and related crimes over the weekend after he shot a woman Saturday evening in Berwyn as she drove on Contention Lane, in a seemingly random attack, authorities said. The woman died of her injuries on Sunday, authorities said.

But hours before, Jahn had called police himself, telling them he thought he was being followed by multiple people and undercover police officers, according to an affidavit. He told police he had a gun in the car. Police arrived at a PNC Bank in Paoli, where Jahn “presented with frantic behavior,” authorities wrote in the complaint.

An officer suggested he voluntarily go to Paoli Hospital for a mental health evaluation, but told him he would have to surrender his gun, which officials say he lawfully owned and had a concealed carry permit for. Police said in the documents he owned three guns.

He refused to surrender his gun, but agreed to go after asking police to escort him. When they arrived at the hospital, Jahn said that the people following him were there; he was allowed to leave, the affidavit states.

Later that night, after the woman was shot on Contention Lane, Easttown Township police responded to a separate incident in Berwyn after someone called to report a disturbance at their home.

A man’s son told him another man, later identified as Jahn , was standing in their driveway, authorities said. The son told officers during an interview Sunday he and his friends heard four gunshots outside the home before seeing Jahn.

The father asked Jahn what he was doing. Jahn told the man he had been waiting for the police. The son filmed the interaction from inside, which showed Jahn “acting erratically in the driveway of the home,” the affidavit said.

He left on foot, and was seen again a few minutes later driving by, where he “proceeded to curse and yell at” the residents, the affidavit said.

After a neighborhood canvass on Sunday, authorities tracked Jahn’s vehicle using traffic cameras, which showed him driving in the areas where witnesses said he was, including where the woman was shot.

Also on Sunday, a relative of Jahn’s called emergency services for a wellness check on Jahn, who was at the relative’s house saying that someone was out to get him. Police responded and searched the home, and found guns and a dashcam. Police detained Jahn outside the residence. In custody, Jahn made comments that “were erratic and nonsensical,” according to the affidavit.

“Jahn also stated that he pulled the trigger at the car and that he definitely did that and then reiterated the statement a short time later,” officers wrote in the affidavit.

Chester County District Attorney Chris de Barrena-Sarobe announced the charges against Jahn on Monday. Investigators believe that Jahn did not know the victim and that he acted alone. There is no ongoing threat to the community, de Barrena-Sarobe said.

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