i was detained by customs and informed that there was a warrant for my arrest by the US Army. The customs agent contacted military police and while waiting for them to pick me up proceeded to make me fill out a form. I didn't read it because i was too nervous but i still filled it out. Only thing i noticed is that the form indicated not to be filled out be citizens or legal residents. I asked the agent why i needed to fill it out and he said that in case i get charged with desertion which is a "deportable" crime, they would start process to deport me. When the military police picked me up, the agent never returned my green card or passport. Is that legal or he violated due process? Also, can i get deported although i received an administrative discharge from the Army?