Your defense of DHS is so lame. The job of DHS is to adjudicate these cases right away, assuming that there is need for such adjudication.
It's not up to the DHS to adjudicate, that's the courts and ALL accused have the legal right to have their case heard before a jury, basic Constitutional Right for all persons accused within the US. Most of the time they will plea guilty and can be deported but for the ones who know the system they play it to the hilt.