Ohio Treasurer Josh Mandel is right to have started a thorough investigation of investments made under his predecessor from 2009 through 2010. Mandel should take out an insurance policy by asking for an independent probe, too.
Last month, former Deputy Treasurer Amer Ahmad was indicted in federal court on eight charges including bribery and money laundering. Ahmad served under former Treasurer Kevin Boyce.
Clear conflicts of interest were involved in some decisions made by Ahmad. For example, he had close personal ties with a lobbyist whose firm he chose to invest $32 million in pension funds.
But if federal prosecutors are right, much worse occurred. One accusation is that Ahmad authorized a high school classmate, Douglas E. Hampton, to handle securities trades for the state. Then, prosecutors say, Hampton kicked back $123,623 to Ahmad.
After leaving the treasurer's office, Ahmad landed a job as Chicago's city comptroller - partly on the strength of a recommendation from Boyce. When he made it, Boyce was aware Ahmad was under investigation.
After learning Ahmad was indicted, Mandel announced he would conduct a ''top-to-bottom review'' of matters handled by the former deputy treasurer. Initially, he said his office would deal with the review.
But Mandel would do well to bring in an independent investigator, too, because of the political ramifications of the matter.
Mandel is a Republican. He was elected treasurer by defeating Boyce, a Democrat. And Ahmad was initially hired in 2008 by former Treasurer Richard Cordray, a Democrat who was picked by President Barack Obama to direct the federal Consumer Financial Protection Bureau.
No doubt Mandel's staff will dig out plenty of dirt involving Ahmad - and possibly other people. Use of an independent investigator could avoid accusations Mandel's probe is politically motivated.
One way or another, a question Mandel needs to answer is how Ahmad, if guilty of the charges against him, got away with his misdeeds. Then, Mandel needs to be able to reassure Ohioans safeguards have been put in place to avoid similar wrongdoing in the future.