The WSJ reports this morning that SEC Chairman Chris Cox has recused himself from the agency’s probe of Senate Majority Leader Bill Frist’s sale of stock in HCA – a for-profit hospital chain founded by members of Frist’s family. Cox, who recently took over at the SEC after years as a California congressman, cited both his service with Frist as part of the Republican leadership in Congress and the need to avoid the appearance of impropriety.

As the Journal adds, the recusal means that “Cox won’t be able to direct the investigation or be briefed on it. He also will have to abstain from voting on any enforcement action related to the case, including issuing subpoenas or filing charges, should the staff make such recommendations. That leaves the investigation in the hands of the SEC’s four other commissioners – two Democrats and two Republicans.”

Meanwhile, the Justice Department is also investigating Frist’s sale of stock of the stock – his ownership of which he was aware despite its being held in what has been described as a “blind trust” – a few weeks before its value declined by about 9 percent.