back door draft
 n.— «One individual advised that he is being involuntarily recalled for placement in the Army Reserve, despite having been out of the Army for over two years. Apparently the referenced action is being taken because of the Army’s ongoing manning problems. I’m aware of the continuing liability for recall after separation, but among some of my correspondents the news that this “back door draft” is actually occurring was understandably greeted with surprise and concern.» —“Re: Recalls Occurring; Seeking More Info” by Lee Knoper Usenet: alt.military Apr. 5, 1999. (source: Double-Tongued Dictionary)