President Trump signed an order on Friday evening barring transgender individuals from joining the military. However, it also gives Defense Secretary Jim Mattis discretion to determine whether current transgender personnel can continue to serve. An estimated 2,000 to 11,000 active duty and reserve troops are transgender, according to a 2016 study by the RAND Corporation. Mattis has some six months to develop a plan to implement the administration's directive. "The Department of Defense has received formal guidance from the White House in reference to transgender personnel serving in the military," DOD spokesperson Dana White said. "More information will be forth coming."