Complex sentence: The amount of undocumented immigrants in the US is over 12 million in total and those that argue against the PIC claim that effective immigration policy has failed to pass since private detention centers profit from keeping undocumented immigrants detained.
Split into simpler sentences: The amount of undocumented immigrants in the US is over 12 million in total. Those that argue against the PIC claim that effective immigration policy has failed to pass since private detention centers profit from keeping undocumented immigrants detained.