administrative detention
... that at any given time, the United States holds as many as 31,000 illegal immigrants in administrative detention while they await removal proceedings?
... that at any given time, the <a href="./United_States" id="mwAik" rel="mw:WikiLink" title="United States">United States</a> holds as many as 31,000 <a class="mw-redirect" href="./Illegal_immigrants" id="mwAio" rel="mw:WikiLink" title="Illegal immigrants">illegal immigrants</a> in <b id="mwAis"><a href="./Administrative_detention" id="mwAiw" rel="mw:WikiLink" title="Administrative detention">administrative detention</a></b> while they await removal proceedings?