The particular method Immigration and Customs Enforcement (ICE) uses to report the facility-by-facility detainee population seems to be underestimating actual detention levels. For some facilities, ICE’s numbers amount to an undercount of not dozens, but hundreds of detainees.
My colleague Austin Kocher and I have developed a method for obtaining a more up-to-date estimation of how many people ICE is currently detaining. We call it Interval Average Daily Population, or Interval ADP.
Instead of restating the details here, I suggest you go to Austin’s substack to learn more. If you want to get into the nitty-gritty of the Interval ADP method, I have attached a link to the white paper here, or go to the home page of Relevant Research.