We're pleased that the Mercer County Board last week hired a firm to begin a forensic audit of the county treasurer's office for two reasons.

First, because as we suggested after Treasurer Mike Bertlesen was arrested on felony theft charges, even though the allegations had nothing to do with county funds, we believed an in-depth examination of treasurer's office accounts was important to ensure that public confidence in the office is not misplaced.

Second, so that it gives us an opportunity to again urge Mr. Bertelsen to step away from the office until charges that he took $800 from the Mercer County Republican Central Committee can be cleared up.

Initially, county officials declined to approve the forensic audit recommended by State's Attorney Greg McHugh, citing high costs. Instead, the board's finance committee decided to await results of a more in-depth look at the Treasurer's books by regular auditors before making such a move. On Thursday night, after a brief closed session, the board voted unanimously to hire McGladrey and Pullen LLP, Peoria, to begin the first phase of a forensic audit.

Mr. Bertelsen, who pleaded innocent to the charge on Oct. 1, is free on bond and has returned to work in the treasurer's office in Aledo. Surely the presence of forensic accountants digging into the books will make it even harder for him to carry out his daily duties.

We again strongly urge him to take a leave of absence from the job. By doing so, he is not admitting guilt. Indeed, we once again remind readers that he must be presumed innocent unless proven guilty in a court of law.

But, as we noted in September, a theft case against its top money manager could be a serious distraction for a county trying to find its financial footing.

The presence of investigative auditors won't make it any easier to focus on the office's key fiduciary duties. If Mr. Bertelsen truly wishes to serve taxpayers, which has done since 1994, he should step away, at least until the results of the forensic audit are revealed.