ICE data codebook

Authors

Affiliations

Graeme Blair

University of California–Los Angeles

David Hausman

University of California–Berkeley School of Law

Phil Neff

University of Washington Center for Human Rights

Published

December 10, 2025

We provide a codebook for the main ICE data tables and fields. The codebook is a work in progress; there are many things we do not understand in the data, and some of our educated guesses here may be mistaken. We will continue to update the codebook as we learn more, and we welcome feedback and corrections.

This codebook reproduces parts of a preprint article that describes the ICE data we have posted.

Data structure

In the arrests, detainers, encounters, and removals tables, each row represents a single enforcement action taken by ICE for a particular noncitizen. In some cases, noncitizens appear more than once in the data, because some are arrested, encountered, or removed more than once (if they are removed and reenter the country).

The detentions table is more complex. Each row in the original ICE detentions data represents a single “stint” in detention at a particular detention center. Most noncitizens have only one stint per stay in detention, but some are transferred between detention centers during a single stay.

To illustrate the data structure of the detentions table, we take two noncitizens as examples:

Noncitizen A is detained from March 19 to March 21. They have a single stint in Otero County Processing Center. They have one stay and one stint within the stay.
Noncitizen B is detained once, from June 6 to July 9, but during their stay in detention they are transferred between three facilities. They have a first stint at the Los Angeles ICE hold room (“LOS CUST CASE”) from June 6 to June 7, then they are transferred to Adelanto ICE Processing Center and held there from June 7 to July 25, and finally they are transferred to Desert View Annex and held there from July 25 to July 9. Noncitizen B has one stay with three stints.

These two citizens’ stays in ICE detention would be represented in the stint level dataset provided by ICE like this:

	Noncitizen ID	Stint ID	Stay dates		Stint dates		Detention facility
	Noncitizen ID	Stint ID	Book-in	Book-out	Book-in	Book-out	Detention facility
Stay 1	A	1	Mar. 19	Mar. 21	Mar. 19	Mar. 21	OTERO CO PROCESSING CENTER
Stay 2	B	1	Jun. 6	Jul. 9	Jun. 6	Jun. 7	LOS CUST CASE
	B	2	Jun. 6	Jul. 9	Jun. 7	Jun. 25	ADELANTO ICE PROCESSING CENTER
	B	3	Jun. 6	Jul. 9	Jun. 25	Jul. 9	DESERT VIEW ANNEX

The Deportation Data Project provides a processed version of the detentions data at the stay level. The two citizens’ stays in ICE detention would be represented in the stay level dataset like this, as two rows:

	Noncitizen ID	Stay dates		# of Stints
	Noncitizen ID	Book-in	Book-out	# of Stints
Stay 1	A	Mar. 19	Mar. 21	1
Stay 2	B	Jun. 6	Jul. 9	3

Tables

We describe the main ICE data tables below.

Fields (variables) in latest data release

We describe the fields (a.k.a. variables or columns) in the latest ICE data release below. The table includes the name of each field, a description, and the type of data in the field (e.g., string, numeric, date). Expanding a row will show an indicator for whether the field is available in each table and the proportion missing.

Fields (variables) in previous data releases

We also provide a table of fields (a.k.a. variables or columns) that were available in previous ICE data releases but are not included in the most recent data. This table includes the name of each field, a description, and the type of data in the field (e.g., string, numeric, date).

Citation

BibTeX citation:

@article{blair2025,
  author = {Blair, Graeme and Hausman, David and Neff, Phil},
  title = {Immigration and {Customs} {Enforcement} {Individual-Level}
    {Data:} {An} {Introduction}},
  date = {2025-12-10},
  url = {https://deportationdata.org/docs/ice/ice-data-preprint.pdf},
  langid = {en}
}

For attribution, please cite this work as:

Blair, Graeme, David Hausman, and Phil Neff. 2025. “Immigration and Customs Enforcement Individual-Level Data: An Introduction,” December. https://deportationdata.org/docs/ice/ice-data-preprint.pdf.