Which federal agencies investigate wrongful detentions by ICE and what powers do they have?

1. DHS’s internal oversight: who can open files and what they can do

DHS’s own internal oversight offices — the offices members of Congress have explicitly asked to investigate ICE’s handling of citizen encounters — can audit, request documents, interview personnel, and produce reports that pressure reforms inside the department; lawmakers requested those offices look into wrongful detentions and training practices ^[1]. Those internal bodies can recommend discipline or policy changes but lack independent criminal prosecutorial power, meaning their findings typically feed referrals to prosecutors or fuel congressional oversight rather than by themselves securing criminal charges ^{[1] [3]}.

2. The Department of Justice, U.S. Attorneys, and the FBI: criminal and civil enforcement

When conduct potentially violates federal criminal statutes — most notably civil‑rights statutes like 18 U.S.C. § 242 — DOJ and U.S. Attorneys have authority to open criminal investigations, convene grand juries, and pursue prosecution; legal commentators and oversight advocates have argued that DOJ enforcement of those statutes has been uneven in immigration cases and that silence from DOJ can amount to abdication of enforcement responsibility ^[2]. The FBI can investigate violent or potentially criminal acts by federal agents and typically works with the U.S. Attorney’s Office; in high‑profile incidents the FBI and state agencies have initially collaborated before federal prosecutors assert jurisdiction ^[2].

3. Federal courts and judges: injunctions, consent decrees, and constitutional remedies

Courts can review arrests and detentions for constitutional violations, issue injunctions, enforce consent decrees, and order remedies when ICE’s practices breach legal obligations; recent federal rulings have found warrantless arrests violated court orders, extended consent decrees, and forced ICE to revise nationwide guidance on probable cause ^[4]. Judicial relief also undergirds civil suits seeking damages or declaratory relief, though plaintiffs face doctrinal hurdles — for example, Bivens claims against federal agents and FTCA claims against the government are available but limited by precedent and procedural prerequisites ^{[5] [6]}.

4. Congressional oversight: subpoenas, reports, and political leverage

Congressional committees can compel documents, hold hearings, demand investigations of ICE and DHS internal offices, and publish reports that shape public pressure and legislative remedies; members of Congress have publicly demanded investigations into ICE’s detention of U.S. citizens and asked DHS oversight offices to act ^[1]. Senate investigations and committee reports — such as a Senate Homeland Security and Governmental Affairs report highlighting arbitrary detentions — have documented patterns of conduct and can prompt referrals, statutory changes, or budgetary constraints ^[3].

5. Administrative and civil pathways: FTCA, Bivens, and structural limits

Individuals seeking redress can pursue administrative claims under the Federal Tort Claims Act and constitutional claims under Bivens, and Congress has been urged to create clearer private rights of action; however, FTCA requires a detailed administrative claim and waiting period, Bivens relief is narrow and often blocked by sovereign‑immunity doctrines, and commentators warn those remedies are imperfect backstops when systemic enforcement failures exist ^{[5] [6]}. These limits make criminal prosecution or sustained congressional pressure often the most consequential leverage points.

6. Practical contours and political realities

Power is distributed but not always exercised: DOJ discretion, political direction of DHS, and internal agency investigations determine whether investigatory findings translate into prosecutions or discipline — critics argue DOJ has sometimes been silent in the face of alleged excessive force and that ICE’s internal processes have been insufficient to check abuses ^{[2] [3]}. At the same time, statutes authorizing delegation of immigration functions (such as 8 U.S.C. §1357 and related administrative delegations) complicate accountability when state or other federal actors perform enforcement duties ^{[7] [8]}.

Conclusion: remedies exist across multiple agencies — DHS oversight, DOJ/FBI, U.S. Attorneys, Congress, and the federal courts — but each actor brings distinct authorities and limitations, and meaningful accountability frequently depends on coordination between investigators, prosecutors, and judges as well as the political will to use those powers ^{[1] [2] [4] [3] [5]}.