However, the ABC7 I-Team has learned that Peterson's suspension was a result of hiding weapons for his father Drew, including an illegal AR-15 assault rifle.
A source familiar with details of the Peterson case told the I-Team on Saturday that it was Stephen Peterson's testimony about accepting the weapons from his father that prompted the first move toward termination. "We believe he was obligated to turn them in" to authorities the law enforcement source said.
In testimony last Monday, Stephen Peterson admitted to taking possession of the assault rifle and at least one other weapon his father did not want the state police to find.
Stephen Peterson held onto the guns for four days, even after state police raided his father's Bolingbrook home with warrants to search for guns.
It was on Oct. 30, 2007 that Drew Peterson delivered the guns to his son's North Aurora home. That was the day after Peterson's fourth wife Stacy was reported missing. She has never been located and detectives believe Drew Peterson killed her and disposed of the body.
From the witness stand last week Stephen Peterson said the weapons were among his father's "favorites," and that "he didn't want anything to happen to them."
Drew Peterson remains in jail, charged with the murder of his third wife Kathleen Savio and on a felony gun charge for allegedly possessing a short-barreled assault rifle. His son does not face criminal charges even though he has admitted possessing and hiding the guns. The I-Team on Saturday was told by an investigative source that an outside law enforcement agency is currently examining Stephen Peterson's conduct.
This is not the first time Drew Peterson's police officer son has been in trouble. Stephen Peterson has been suspended on at least five occasions in his short career. His resume of punishment includes a suspension in April, 2008 for violating Oak Brook Police Dept. rules. He wore his police uniform and used a village squad car to drive to Joliet for his appearance in front of a Will County grand jury that was investigating his father.
That suspension followed an I-Team report in Dec. 2007 that Illinois state investigators had subpoenaed the personnel files of three men with connections to the village of Oakbrook Police Department. Among them was Steve Peterson.State authorities removed Steve Peterson's police personnel file and other records of his patrol activities during key period of his step-mothers' disappearances. In 2007 the I-Team was by investigators that state police seized the Oakbrook department personnel files of two of Peterson's closest friends on the force. One had resigned while under investigation for professional misconduct. The other was terminated for lying and unauthorized access of criminal files.
Those who know Drew and Steve Peterson say the men are more like best friends than father and son. Drew was Steve's best man at his wedding in 2007. Stephen Peterson's wife Teresa is a federal agent with the inspector general's office for the U.S. Housing Department.
Teresa Peterson was also questioned by investigators in 2007 as to her husband's whereabouts and activities during certain key periods of time.
Neither Oak Brook police officials nor Peterson have been available for comment. Drew Peterson's attorney Joel Brodsky called the suspension "pure vindictiveness" and "baseless."