Culver's personal SUV involved in traffic stop Sunday

(AP) - An Iowa State Patrol trooper driving Gov. Chet Culver and his 7-year-old son in an unmarked vehicle tried to pull over a driver who was "screaming down the highway, honking the horn" and nearly hit the governor's vehicle, public safety officials said Tuesday.

The attempted stop happened Sunday afternoon in West Des Moines and led to a roughly 6-mile chase that didn't exceed the speed limit and ended when police in marked cars showed up.

Trooper Mike Clyde turned on the sport utility vehicle's red and blue lights and tried to stop the car because of how the driver was acting, Iowa Department of Public Safety spokeswoman Courtney Greene said.

"The trooper at that point didn't know if the person was under the influence or what was going on," Greene said. "If they think there's a threat to public safety, they use their best judgment to decide how to handle it, and that's what the trooper did."

Greene said it was the first time that she knew of a trooper assigned to the governor stopping a motorist. Clyde, who has been with the executive protection unit since 2007, remains on the job, the agency said.

The driver, Ed Allen of West Des Moines, was allowed to leave and wasn't cited. He told police he didn't know that the trooper, who was in plain clothes, was a law enforcement officer. Allen later filed a complaint against the trooper, but he declined to comment when called Tuesday by The Associated Press. The complaint wasn't made public.

The incident began on a major street in West Des Moines, when Allen cut off the governor's SUV and acted erratically, Greene said. Allen was driving the speed limit but refused to stop, Greene said.

The governor's driver called for assistance from West Des Moines police, which sent three marked squad cars to the scene, Greene said.

The incident ended when the driver saw the police cars and stopped. His wife, Melissa, and two children, ages 8 and 12, also were in the car, police said.

Allen filed a complaint against the trooper with the Department of Public Safety's professional standards bureau, which is investigating. Iowa State Patrol director Col. Patrick Hoye will make the final call.

"There isn't any allegations of criminal conduct here. It's a personnel or a professional complaint," Jessica Lown, another Department of Public Safety spokeswoman, said. She declined to detail the complaint.

"We trust them to handle this in the appropriate manner," the governor's spokeswoman, Polly Carver-Kimm, said but declined further comment. Culver was in Cedar Rapids on Tuesday campaigning for re-election with Vice President Joe Biden.

Some of the incident was captured on a video recorded by a camera in a West Des Moines patrol car. The video, which has no audio, shows Culver and his son, John, getting out of the SUV after the chase and walking toward the police car, while police officers walk toward the governor's vehicle and the car. The video was obtained by KCCI-TV in Des Moines.

"Talking to the officers involved in that incident, the guy stopped and said he didn't know that he was a cop. He said he saw the unmarked black car, the guy in plain clothes and saw the blinking lights," West Des Moines Lt. Jeff Miller said. "He goes 'I have my family with me and I'm not going to stop.'"