Exactly one week after the FBI took possession of Hillary Clinton's personal email server, Al Jazeera America has been told that the FBI is now treating the Clinton case as a potential criminal investigation. Our sources add that dozens of federal investigators have now been assigned to this investigation.

Several weeks ago, when Inspectors General referred the Clinton email controversy to the Justice Department for review, the DOJ knocked down suggestions reported in the New York Times at the time that this was a criminal referral. The Inspectors General backed up the claim that their referral was administrative rather than criminal. However, the FBI — the agency responsible for investigating Clinton's server — now believes there may be a criminal case to answer.

Clinton's primary defense, reiterated on Tuesday, has been that none of the government emails she possessed had been marked or identified as “classified.” But as Al Jazeera’s story points out, a violation of the relevant criminal code statute (18 USC Section 1924) does not require that material be marked or stamped as “classified.” In other words, Clinton's public defense may help her politically, but it wouldn’t necessarily suffice in the event of a criminal case.