Understanding ICE’s Detention Numbers

ICE releases detention statistics on a bi-weekly basis. For the past year, we at TRAC have been systematically collecting that data to provide further insight into the immigration system.

One immigration detention statistic that can be confusing is the number of people in detention versus the number of new people put into detention called “book-ins.” Using a running total of the average daily detention population per month and the total number of monthly book-ins, we can see how these two numbers give slightly different but interrelated perspectives on detention.