U.S. Immigration and Customs Enforcement: Actions Still Needed to Improve Planning and Management of Its Native American Law Enforcement Unit

What GAO Found

Within U.S. Immigration and Customs Enforcement (ICE), the Shadow Wolves program operates on the Tohono O'odham Nation reservation in Sells, Arizona. In January 2024, GAO recommended that ICE define the mission and goals of the program, with input from the Tohono O'odham Nation. GAO also recommended that, ICE determine the staffing needs for the program on the Tohono O'odham Nation reservation, to include the skills and number of positions necessary. ICE concurred with the recommendations.

In July 2024, ICE defined the program's mission. However, ICE had not discussed the mission and goals of the program with the Tribe as of September 2025. In addition, ICE's defined goals for the program do not align with the program's mission or describe the results it hopes to achieve. Further, though ICE has defined staffing goals for the program, it has not yet performed a workforce analysis to determine the program's staffing needs, including the number and type of personnel the unit needs to meet operational demands. GAO maintains that defining operational goals linked to the program's mission with input from the Tohono O'odham Nation can better position ICE to ensure that operations achieve desired outcomes and ensure that ICE and the Tohono O'odham Nation have a common understanding of the program's mission. Clearly defining the Shadow Wolves program mission and establishing operational goals are particularly important in light of continued differing perspectives and lack of clarity on the mission and activities of the program on tribal lands.

The number of Shadow Wolves has declined over time as shown in the figure below. In January 2024, GAO recommended that ICE update its October 2022 Shadow Wolves recruitment strategy to include measurable goals, timelines, and milestones, and develop a succession plan to address upcoming retirements. ICE concurred with these recommendations and has taken steps to recruit Shadow Wolves, such as posting a job announcement seeking applications for Shadow Wolves personnel in September 2025. While this is a positive step, GAO maintains that ICE should also (1) develop and document measurable goals, timelines, and milestones so that officials can review progress of their recruitment efforts and make any needed adjustments and (2) develop a succession plan to better ensure that experienced Shadow Wolves will be available to train new recruits.

Number of Shadow Wolves, Calendar Years 2003 to 2025

In January 2024, GAO also recommended that ICE develop criteria for evaluating possible additional Shadow Wolves locations. ICE concurred with this recommendation and has taken some steps to implement it. In July 2024, it broadly defined elements that would enable it to select new locations, including: the willingness of partnering Tribal Nations, levels of criminal activity, and the availability of funding. However, ICE had not detailed how it will apply these broad criteria to selecting potential locations. As of August 2025, ICE officials said expansion efforts had been placed on hold due to a lack of funding for Shadow Wolves positions outside of Sells, Arizona. GAO maintains that, moving forward, developing criteria for evaluating and selecting expansion locations could help ensure that ICE evaluates locations consistently while improving transparency of the process.

Why GAO Did This Study

About 62 miles of the U.S. southwest border is located on the Tohono O'odham Nation reservation, which may be vulnerable to illicit cross-border activity. The Shadow Wolves program began operations in 1974 to address the illegal smuggling of controlled substances from Mexico to this reservation in Arizona. The unit currently operates within ICE's Homeland Security Investigations (HSI). The program's employees-known as "Shadow Wolves"-must be certified to have at least one-quarter American Indian ancestry from a federally recognized Tribe.

The Shadow Wolves Enhancement Act, which became law in April 2022, includes a provision for GAO to assess the effectiveness of ICE's strategy for the Shadow Wolves program not later than 1 year after receiving the strategy, and annually for the following 2 years. GAO issued its first report related to this provision in January 2024 and the second report in November 2024. This report assesses ICE's (1) efforts to define the mission of the Shadow Wolves program and conduct workforce planning to understand the skills and positions necessary to meet mission needs, (2) strategies for recruiting and retaining Shadow Wolves, and (3) planning efforts to expand the program to other tribal lands. GAO conducted interviews with ICE and HSI headquarters officials, HSI field officials, and each member of the Shadow Wolves unit regarding program operations, mission, retirement plans, and expansion planning efforts.