CORVALLIS, Ore. -- A police officer who resigned amid complaints that he was overzealous in pursuing drunken drivers is now helping such motorists beat the rap in court.

Dave Cox, who resigned from the Corvallis Police Department on Nov. 1., works in Boise, Idaho, as the proprietor of Fact Finder Investigations Inc., an agency that specializes in the defense of DUII cases.

Many Oregon drivers could have used such help during Cox's six years as a Corvallis patrol officer. Cox made more than 1,000 impaired-driving arrests -- way more than anyone else on the force. He was so prolific that he won a statewide award.

But his police career crashed after an internal investigation found he had wrongfully arrested a sober man. The local district attorney later declined to prosecute about 100 cases because they relied on Cox's testimony.

Cox is also a co-defendant in two civil lawsuits against Corvallis alleging false arrest for DUII.

Reached by the Gazette-Times newspaper last week, Cox said he would not discuss his new line of work with the press.

His company's Web site touts his extensive law enforcement training in catching impaired motorists and offers to put that expertise to work for those facing charges of driving under the influence.

Cox charges $255 for a DUII defense case review or $85 an hour for trial prep. He also offers to testify as an expert witness or re-create the events on the day of the arrest.

Cox has also developed a seminar for defense lawyers. Highlights include sections on how to attack the results of a breath test and the tricks and tactics police use in drunk-driving cases.

Local law enforcement officials said Cox's business venture does not surprise them.

"It's not uncommon for folks who once worked in law enforcement, once that's not an option for them, to go into some other sort of investigative work," said Benton County District Attorney John Haroldson. "There's nothing improper about that."