The FBI is presently conducting a security inquiry into the email matter, and not a criminal investigation. The FBI is regularly requested by various federal agencies and departments to conduct security inquiries. But hypothetically and for argument's sake, since it's already been established that Secretary Clinton was the recipient of those emails which were classified two-plus years after they were first sent, and was not the point of origin, if anyone were indeed under threat of criminal indictment, it would very likely be those State Dept. employees who first sent the now-classified information, and not the person who was the unknowing recipient.