How have prosecutorial discretion memoranda under different administrations affected who ICE prioritizes for arrest and removal?

1. What prosecutorial discretion memos do — and what they cannot do

Prosecutorial discretion memos do not rewrite immigration law but instruct DHS and ICE where to concentrate finite enforcement resources, telling officers which removable noncitizens should be highest priority for arrest and removal while leaving statutory arrest and detention authorities intact ^{[1] [3]}. These memos therefore create operational rules — who to seek in the interior, when to detain versus release to Alternatives to Detention, and which categories (e.g., national‑security, public‑safety, border‑security threats) get top priority — but they cannot remove ICE’s statutory powers to arrest or the role of state and local cooperation where those exist ^{[1] [3]}.

2. The “prioritize threats” pivot under the Biden-era guidance

In 2021 DHS updated its policy to concentrate enforcement on noncitizens deemed threats to national security, public safety or border security, a shift meant to focus limited resources and reduce interior arrests of low‑risk immigration violators ^[2]. That guidance correlated with ICE framing enforcement as targeted and intelligence‑driven, and with public messaging about increased use of Alternatives to Detention rather than blanket detention of those with final removal orders ^{[3] [5]}. Independent reviews show this change coincided with fewer removals overall despite continued arrests, underscoring that prioritization can reduce enforcement intensity for lower‑risk groups even when statutory authority remains ^[2].

3. Broad enforcement under administrations that direct “all removable” action

When an administration instructs ICE to act against all removable noncitizens, policy produces broader interior targeting and greater reliance on arrests drawn from criminal‑justice touchpoints and local jails; DHS policy from 2019 through January 2021 directed ICE to take enforcement action against all removable noncitizens, and later administrations reversed toward narrower priorities ^[2]. More aggressive directives—such as those reported under the Trump administrations’ return to broad interior enforcement and explicit public goals in 2025—have produced surges in public arrests, a push to retrieve people from local jails, and high‑visibility operations that critics say amplify fear in immigrant communities ^{[6] [7] [4]}.

4. How guidance translates into practice: data, local partners and limits

The real-world effects of memos have been mediated by ICE capacity, cooperation from local law enforcement, and data reporting limits; GAO documented varying arrest and removal numbers from 2019–2022 and urged better data transparency, noting removals fell even as arrests rose in some years, while Migration Policy and other analysts emphasize that accessing local jails accelerates removals when jurisdictions cooperate ^{[2] [8] [4]}. Advocacy and research groups show that where state and local collaboration is robust, federal priorities—whether narrow or expansive—are easier to translate into high arrest and removal rates, whereas sanctuary policies blunt interior enforcement regardless of federal memos ^{[4] [9]}.

5. Tradeoffs, accountability and the next phase

Prosecutorial discretion memos are powerful levers that alter who ICE targets — narrowing enforcement to public‑safety threats reduces arrests of low‑level immigration violators, while broad memos expand interior enforcement and amplify use of local jails — yet their effects are neither absolute nor purely legal: they interact with funding, field office culture, local partnerships and transparency gaps that shape outcomes ^{[2] [3] [4]}. Courts, state and local policymakers, and watchdogs therefore remain critical check points because memos can steer but not eliminate statutory authority or operational choices that produce the arrests and removals that communities ultimately experience ^{[1] [2]}.