ICE Detention Numbers Decline Slightly for the First Time During the Trump II Administration
Despite total decline, the number of people arrested and detained by ICE rather than CBP continued to grow modestly.
The latest detention data from Immigration and Customs Enforcement (ICE) shows that 48,870 immigrants were held in detention as of May 18, 2025. This represents modest decline from the previous detention total of 49,184 on May 4.
This trend suggests that ICE may have run into funding or facility barriers after the agency’s initial rapid expansion of detention space. As I emphasized previously, even with the growth in total numbers slowing down, ICE is still putting people through the churn of the detention system in ways that are not necessarily reflected in the single-day population total. In any case, ICE’s capacity limitations may not last forever as ICE seeks more funding for detention beds from Congress and possibly begins to delegate detention duties to local sheriffs through 287(g) agreements.
ICE arrests continue to drive detention numbers: 64% of all current detainees were arrested by ICE and 36% were taken into custody by CBP. In April, the most recent data released by CBP, the agency recorded just 12,035 encounters. This number is up slightly from March but remains at historical lows.
The first graph below shows the total number of people in detention arrested by ICE only. The second graph below shows the total number from both ICE and CBP comparatively.
I previously found that the initial growth in ICE’s detained population reflected significant growth among immigrants without criminal histories. That trend tapered off for a few weeks, but is back. The biggest growth in people in detention because of an ICE arrest in the last two weeks were people with no criminal charges or convictions. This fraction overall is still the smallest of the three, but it did increase slightly from 18% to 19%. The graph and table below show two perspectives on the breakdown on this trend.
No Major Data Quality Issues Detected to Date Under Trump II
Note that I added this section after initial publication to address concerns.
I have received a lot of questions recently about whether I believe ICE’s detention data is being manipulated and tampered with in some way. I want to state as unambiguously as possible that I have seen no reason to doubt the quality of data in the ICE detention data spreadsheet. Although I cannot peer behind the curtain to see how this data is produced, I have not seen any anomalies that cause me to doubt the reliability of this data. The Biden administration was incredibly sloppy with this dataset so I hope I would catch tampering if it happened. If I do get a whiff of ICE politicking with this data, I will convey those concerns without hesitation.
Here are some examples of previous data issues I’ve found and how I’ve communicated them.
ICE's Sloppy Public Data Releases Undermine Congress's Transparency Mandate
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I know it's not your job to speculate, but do you have any idea what accounts for a sudden rise in the detention of immigration violators without criminal convictions or pending criminal charges? From January to March is a big jump.