What specific memos or policy directives did the Obama and Trump administrations issue regarding ICE arrest priorities?

1. Obama-era memoranda: “Prioritize the worst threats”

Under President Obama, ICE Director John Morton and related offices produced memoranda in 2010 and 2011 that created a three‑tiered prioritization scheme focused on national security threats, significant criminal offenders, and recent border crossers—explicitly channeling limited enforcement resources toward those categories and instructing ICE to exercise prosecutorial discretion to avoid wasting resources on low‑risk individuals ^{[1] [2]}.

2. How Obama’s guidance worked in practice: supervisory review and discretion

The Obama guidance not only listed priorities but built in supervisory review and processes: agents and ICE attorneys were encouraged to request dismissals or indefinite suspensions for non‑serious cases, and decisions often required Field Office Director review—measures intended to limit interior removals of longstanding residents and low‑level violators ^{[3] [2]}.

3. Trump’s rollback: executive orders and memos that broadened enforcement

President Trump’s January 25, 2017 executive order and follow‑on DHS/ICE memos rescinded the Obama prioritization structure and framed prosecutorial discretion as limited rather than presumptive—directing ICE to target virtually any unauthorized immigrant and instructing attorneys to reopen previously closed cases, especially where criminal history or fraud could be alleged ^{[3] [2]}.

4. The practical effect described by reporting and analysts

Reporting and analysts describe the Trump approach as shifting from “quality over quantity” (Obama’s framing) to a much broader interior enforcement posture that sought to remove people regardless of ties and led to more routine screening and arrests—critics said it reduced the use of discretion and expanded the pool of detainees ^{[4] [5]}.

5. Internal memos vs. public directives: differences in tone and enforcement limits

Independent analyses emphasize a key difference: Obama-era memoranda codified limits and discretionary processes; Trump-era documents emphasized enforcement across a wider group and effectively warned ICE that the prioritized lists should not be construed to prevent enforcement elsewhere—meaning the Trump memos were more permissive and operationally aggressive ^{[3] [2]}.

6. Implementation controversies and consequences

Reporting notes controversy about implementation: critics argued Trump directives led to reopening cases and pursuing removals of people who had long ties or minor offenses, while former Obama ICE officials warned that mass arrest strategies could strain resources and let the most dangerous offenders slip through due to diverted focus ^{[2] [6]}.

7. What the sources do not specify

Available sources do not mention the full text of every single Trump- or Obama‑era memo line‑by‑line in this collection; they summarize the key directives and operational changes but do not reproduce all original documents here ^{[1] [2]}.

8. Competing perspectives and implicit agendas

Advocates for Obama’s approach framed the memoranda as pragmatic triage—maximizing public‑safety returns from finite resources ^[1]. Supporters of Trump’s orders argued broad enforcement restores the rule of law and deters illegal immigration; critics counter that the Trump directives carry an institutional agenda to maximize removals even at the cost of prosecutorial discretion and civil‑liberties concerns ^{[3] [2] [6]}.

9. Bottom line for readers

If you want the concrete policy touchstones: look to the Obama-era John Morton memoranda (2010–2011) and related prosecutorial‑discretion guidance as the documents that narrowed ICE priorities, and to the January 2017 executive order and subsequent ICE memos (and DHS guidance) as the policy instruments that largely rescinded those limits and broadened enforcement ^{[1] [3] [2]}. For full primary‑text detail, consult the original ICE/DHS releases or the memos cited in policy analyses ^{[1] [2]}.