Can state governments investigate or prosecute treason, or is it exclusively federal?
Executive summary
State governments can and historically have prosecuted treason against the state; most state constitutions include a treason clause and some statutes mirror the federal definition, but state treason prosecutions are extremely rare—by most accounts only a handful of state-level treason prosecutions have ever been completed [1] [2]. The U.S. Constitution defines treason against the United States and federal treason prosecutions proceed in federal court under strict rules (two-witness/confession requirement), while scholars and case histories show parallel state treason laws and occasional state prosecutions [3] [4].
1. Treason is written into both federal and many state texts
The U.S. Constitution defines treason narrowly—“levying War” or “adhering to their Enemies”—and requires either a confession in open court or testimony from two witnesses to the same overt act; that constitutional Treason Clause governs federal treason prosecutions [3]. Most state constitutions likewise include treason provisions that track or echo the federal formulation, so treason is not exclusively a federal textual creation; states possess their own treason language and doctrines [1] [4].
2. Federal prosecutions are the default and better‑known path
Because treason is an offense against the United States, federal authorities historically have brought most treason cases; fewer than 40 federal treason prosecutions appear in U.S. history and convictions are rarer still, making federal treason prosecutions notable but infrequent [5] [1]. Federal statute and practice also provide alternative federal offenses—espionage, sedition, seditious conspiracy, terrorism statutes—that prosecutors commonly use instead of treason because they avoid the Treason Clause’s procedural hurdles [6].
3. States have concurrent power to prosecute “treason against the state”
Legal scholarship documents that states may charge people with treason against state governments and that many states have their own treason analogues; state treason prosecutions played significant roles in earlier American history (e.g., Civil War era and other 19th‑century conflicts) and the literature treats state treason as a parallel doctrine to federal treason [4] [7]. Historical examples cited by academic sources include state treason convictions and prosecutions, though modern use is rare [7].
4. Prosecutorial choice and practical avoidance explain rarity
Practitioners and commentators note two forces that limit treason filings: the constitutional two‑witness/confession rule that makes treason harder to prove at the federal level and the availability of statutory alternatives (espionage, seditious conspiracy, federal conspiracy statutes) that avoid the Treason Clause’s procedural burdens, which has made treason an unattractive tool for modern prosecutors [6] [8]. State officials face similar practical problems and thus seldom invoke state treason statutes [6] [1].
5. Counting state treason prosecutions: tiny numbers, disputed totals
Several secondary sources state that only a very small number of state treason prosecutions have ever been completed—some say only twice, others describe “only three” state‑level charges—indicating that exact counts vary across accounts and depend on definitions and historical scope [1] [2]. Scholarly work emphasizes the parallel history but concedes modern prosecutions are almost non‑existent [4] [2].
6. Where authority matters in practice: jurisdiction and remedies
When an act is framed as treason against the United States, federal courts and the Department of Justice normally exercise authority; when an act is framed as treason against a commonwealth or state, state prosecutors can theoretically investigate and try the case under state law [3] [4]. Available sources do not mention a modern, widely used mechanism by which states routinely transfer or coordinate exclusive treason prosecution responsibility with the federal government beyond ordinary federal‑state cooperation (not found in current reporting).
7. Bottom line for readers and policymakers
Treason is not exclusively federal on paper: states have treason provisions and have sometimes prosecuted treason against state governments, but in practice treason prosecutions today are overwhelmingly the province of federal law or are supplanted by federal statutory offenses because of constitutional proof requirements and prosecutorial preference [1] [6] [4]. The historical record and legal scholarship both stress the dual‑sovereignty reality—parallel state and federal treason laws exist even if modern use is vanishingly rare [4] [2].