Kirk, a co-founder of Turning Point USA and ally of President Donald Trump, was killed while speaking at an event at Utah Valley University on Sept. 10.
ICE attorneys wrote in a letter on Friday that the Maryland resident had listed at least 22 countries where he feared persecution if he was deported there.
The clash marks a shift for Moore, who said in a CNN interview earlier this year that he would not be the “leader of the resistance” against the president.