The motorist who fatally ran over a runner in a St. Paul crosswalk was actively using his cellphone for nearly 23 minutes, an uninterrupted span of time that includes the moment of impact, according to a forensic search of his phone cited in a court document filed last week.

In a search warrant affidavit seeking permission to crack open Peter Berge’s Facebook account, police said they have data from AT&T that show “an active data session” from just past 4:03 p.m. on Feb. 22 until shortly after 4:26 p.m. on the phone of the prominent 60-year-old attorney.

Berge hit 35-year-old Scott Spoo at 4:22 p.m., within that phone-use time frame, according to the court filing’s citing of Ramsey County emergency dispatch records.

Spoo, of St. Paul, was an avid runner and bicyclist who had worked for 3M in the Twin Cities for 11 years and was an engineer.

About a week after the crash on Mississippi River Boulevard at Dayton Avenue, Berge was found to have an aggressive form of brain cancer, according to his friend Mike Salovich. He has told police that “his condition was the cause of his impaired behavior” at the time of the crash, the latest court filing read.

Berge, who underwent brain surgery, has not been charged in Spoo’s death. A preliminary breath test showed no alcohol in his system, and he told officers that he hadn’t taken any drugs or medication. Police took blood for toxicology tests. Those results are pending.

Last week’s search warrant application, filed in Ramsey County District Court, includes a motorist who reported driving behind Berge’s BMW on Mississippi River Boulevard and seeing him “driving with his cellphone in his hand ... Berge kept looking down at his phone. The witness stated that Berge was varying his speed including rapidly accelerating and swerving into oncoming traffic.”

At one point, the court filing continued, the witness saw Berge’s car force “one oncoming vehicle off to the shoulder to avoid a collision.”

Squad car camera footage captured Berge in the police vehicle’s back seat making at least one call and “continually” using his phone, an affidavit said. An officer took Berge’s phone, placed it on airplane mode and kept it out of Berge’s reach.

Berge, who was in jail for a few days after the crash, was contacted Wednesday by the Star Tribune and referred questions to his lawyer. His attorney, Chuck Hawkins, did not respond to an inquiry.

In explaining why police want to examine Berge’s Facebook account, the court filing described Berge as “a very active Facebook user with numerous public posts and mobile check-ins.” Police said they are hoping, the search request added, to determine whether he “was actively using Facebook at the time of the crash.”

Judge Richard Kyle Jr. granted police permission to go into Berge’s Facebook account. They have yet to say what they found.

Earlier search warrant affidavits filed in court revealed that Berge collided with a Mini Cooper in Minneapolis minutes before hitting Spoo. The Mini Cooper’s driver told police she had to get Berge’s attention because he apparently was unaware of the collision. The two pulled over and exchanged insurance information.

Berge is the ethics chairman for the Hennepin County Bar Association. He also was web director for Minnesota Continuing Legal Education, a nonprofit established by the Minnesota State Bar Association that develops various educational services for lawyers. A staff member at Continuing Legal Education said he left that job weeks before the crash.

The case was moved to Hennepin County because Berge has been a supporter and contributor to Ramsey County Attorney John Choi’s campaign committee.