Iraqi Police
It would be the height of stupidity not to assume that of the thousands of Iraqis being actively recruited into the police and other security positions that at least some of them are Baathist "ringers." Unfortunately, it would be almost impossible to screen them out ahead of time. One hopes that the overwhelming majority of those in the police and other forces, who are actually working for a free Iraq, will weed them out themselves, since that's the only way it's going to be done.