"Timely Immigration and Customs Enforcement (ICE) data about the custody history of detainees who were deported or released by the government during November and December of 2012 shows wide variation in their detention times.
On a typical work day in this very recent period, the records indicate that ICE detained roughly 1,500 individuals. For four out of every ten of this group — approximately 600 of the total — dispositions occurred very quickly, within three days. And for more than two thirds (70 percent) of the total, ICE custody ended during the first month.
Understandably, for those detainees who did not contest their deportations, detention typically ended quickly for the simple reason that these individuals were no longer in the country. On the other hand, longer detention times often occurred in situations where the individual was able to contest the government's attempts to deport them. Indeed, in a perverse way, individuals who were legally entitled to remain in the United States typically experienced the longest detention times. In fact, for some in this smaller group, their lockup might involve a year or more before they won their cases and were released." - TRAC, June 3, 2013.