Updated 02/19/11 – 5:46 p.m.

OAK BROOK, Ill. (CBS) — The Fire and Police Commission in west suburban Oak Brook voted unanimously Saturday to fire Officer Stephen Peterson from the force.

As WBBM Newsradio 780’s Bob Roberts reports, Peterson, the son of retired Bolingbrook Police Sgt. Drew Peterson, had been on paid administrative leave for six months.

LISTEN: Newsradio 780’s Bob Roberts Reports

The charge that led to the younger Peterson’s dismissal stemmed from the legal troubles facing his father.

As CBS 2’s Pamela Jones reports, the three-member board upheld an accusation that the younger Peterson failed to cooperate fully with Illinois State Police in the days immediately following the October 2007 disappearance of his father’s fourth wife, Stacy.

It specifically cited Peterson’s decision to take posession of a cache of guns as State Police searched his father’s Bolingbrook home, and the younger Peterson’s failure to tell State Police that his father had transferred $236,800 to him for the care of Drew’s four youngest children.

“Officer Peterson’s continuing claim that the weapons and money were irrelevant to the investigation by the Illinois State Police were self-serving, disingenuous, and not credible, and demonstrate that Officer Peterson lacks the fundamental ability to make sound judgments,” said commission Chairman Frederick Cappetta, in announcing the decision.

The charge was one of three departmental rule violations brought against him by Oak Brook Police Chief Thomas Sheahan.

The commission found Peterson not guilty of the other two accusations. One related to his temporary possession of a sawed-off AR-15 assault rifle that his father used in connection with his duties as a Bolingbrook Police SWAT team member. The other accused Peterson of failing to keep the internal investigation into his possession of the guns confidential.

The younger Peterson maintained during the hearings, which began in November, that Sheahan had harassed him for the past three years. Despite that, he said he “loved” his job and hoped to remain with the Oak Brook force.

Peterson and Sheahan refused comment after the ruling.

Peterson’s attorney, Tamara Cummings, called the commission “a kangaroo court” and indicated that her client will appeal the decision to a DuPage County judge. He has 35 days to file notice of appeal.

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