Sources familiar with the matter told FP that once administration officials discovered Jofi Joseph was the staffer behind @natsecwonk and a second account called @DCHobbyist, which tweeted mainly about soliciting prostitutes, he was terminated and his case was referred to DOJ.
One individual briefed on the matter said DOJ was trying to determine whether information leaked by @natsecwonk or any of the behavior described by @DCHobbyist could be considered criminal activity. Joseph had been in the final stages of vetting for a senior position in the Pentagon, according to FP.
Joseph's wife, Carolyn Leddy, is a staffer on the Senate Foreign Relations Committee. According to FP, committee officials were also trying to determine whether any of Joseph's tweets contained classified information provided by Leddy.