What legal standards would need to be met to bring criminal charges against a former president like Barack Obama?

1. Constitutional and doctrinal hurdles: what the courts decide matters most

The Constitution does not expressly say whether a president can be criminally prosecuted, and until recently the Supreme Court had not squarely decided the issue; that left substantial uncertainty that courts and scholars have debated for decades ^{[5] [6]}. In the post‑2024 litigation the Court created a framework distinguishing “core” presidential powers (which it held immune) from other official acts and private acts, meaning prosecutors must show the charged conduct falls outside protected official decision‑making to proceed ^{[4] [7]}. That doctrinal shift is decisive: if alleged behavior is truly a core official act as the Court defined it, criminal charges cannot stand; if it is private or non‑immune official conduct, prosecution remains possible ^[4].

2. Ordinary criminal standards still apply: evidence, grand juries and burden of proof

Separate from immunity, prosecutors must meet traditional criminal standards: a prosecutor needs probable cause to ask a grand jury for an indictment, and a conviction requires proof beyond a reasonable doubt at trial — the same burdens any defendant faces ^[1]. Independent norms and professional rules also constrain charging decisions; organizations like the American Bar Association and DOJ charging policies warn against bringing or declining charges for political reasons, pressuring prosecutors to ground decisions in evidence, not politics ^[8].

3. Immunity and timing: sitting vs. former presidents

The Justice Department historically has taken the position that a sitting president should not be criminally prosecuted — an OLC view dating to the 1970s and reiterated in later memos — but that policy does not categorically bar charges after a presidency ends ^{[9] [2]}. The Supreme Court’s recent rulings, however, have altered the calculus by articulating absolute immunity for core executive acts and presumptive immunity for other official acts, while leaving room for prosecution of purely private conduct; the exact contours are now a matter of litigation and interpretation ^{[4] [7]}.

4. Impeachment, past practice and political realities

An acquittal in impeachment does not automatically immunize a former official from criminal prosecution, a view reflected in Office of Legal Counsel analyses and historical practice that treat impeachment as political and separate from criminal law ^[10]. Yet prosecutorial decisions involving presidents carry extraordinary political salience: critics warn about weaponization of law enforcement and the risk of eroding trust if charges appear partisan, while advocates argue that refusing to prosecute would leave serious wrongdoing unaccountable—both realities shape charging choices and public reaction ^{[8] [7]}.

5. Practical pathway to charges against a former president like Barack Obama — and limits of available reporting

Based on the reporting, the concrete pathway would require assembling admissible evidence establishing probable cause for ordinary criminal offenses unrelated to protected core acts, securing a grand jury indictment, and surviving immunity challenges under the Court’s three‑part framework; prosecutors must demonstrate the alleged conduct was not an immune official act and meet ordinary burdens at trial ^{[1] [3] [4]}. This analysis is limited to available public reporting and recent court rulings summarized above; sources do not provide case‑specific evidence about any former president, so no factual claim is made here about any individual’s culpability or exposure to charges beyond those general legal standards ^{[5] [6]}.