What is the process for removing a member of Congress from office for treason?

1. Two different tracks: impeachment vs. expulsion

The Constitution’s impeachment language—removal on “Impeachment for, and Conviction of, Treason, Bribery, or other high Crimes and Misdemeanors”—applies expressly to the President, Vice President, and “civil Officers,” and it prescribes a House charge and a Senate trial with a two‑thirds conviction threshold for removal ^{[1] [2]}. By contrast, Article I gives each chamber authority to “expel a member” by a two‑thirds vote; congressional precedent and historical practice treat expulsion as the primary internal remedy to remove a Representative or Senator from office ^{[3] [4]}.

2. Why members of Congress aren’t usually impeached

Congressional history and the Constitutionally informed practice indicate that members of Congress are not “civil officers” for impeachment purposes; early impeachment practice (e.g., the Blount case) established that impeachment was not the standard route to remove sitting legislators, and instead each chamber controls discipline and expulsion ^{[5] [4]}. The Constitution’s drafters and subsequent practice left impeachment for executive and other civil officers while reserving member removal to the chambers themselves ^{[6] [5]}.

3. Expulsion procedure and precedent

Article I, Section 5 empowers each House to “determine the Rules of its proceedings, punish its members for disorderly behavior, and, with the concurrence of two‑thirds, expel a member” ^[3]. In the Republic’s history, Congress has expelled 21 members (15 senators, six representatives); 17 expulsions were for Confederate support in 1861–62, demonstrating that expulsion has been used mainly for extreme betrayals of the Union, though other grounds have occurred ^[3].

4. Criminal charges and separate remedies

Neither impeachment nor expulsion is mutually exclusive with criminal prosecution: impeachment is a remedial, political process focused on removal (and sometimes disqualification from future office), while criminal trials and convictions proceed (or can proceed) in the courts under ordinary criminal law ^{[1] [7]}. Available sources emphasize that impeachment/removal does not replace due process in courts; treason and bribery have legal definitions, while “high Crimes and Misdemeanors” is intentionally broad and politically interpreted by Congress ^{[8] [9]}.

5. Standards, definitions, and political discretion

Treason is defined in the Constitution but has a specific legal meaning; bribery has statutory definitions; “high Crimes and Misdemeanors” is not defined and has long been debated—Congress exercises political discretion when deciding what conduct qualifies for impeachment or other sanctions ^{[9] [8]}. The House’s sole power to impeach and the Senate’s role as the tribunal mean political judgment and evidentiary standards vary across cases ^{[10] [2]}.

6. What steps would actually be taken if a legislator were accused of treason

Available sources do not describe a single uniform sequence for removing a member of Congress for treason; they set out two separate mechanisms: (a) the member’s chamber could initiate an expulsion resolution, investigatory committee work, and then vote to expel by two‑thirds ^[3]; (b) separately, prosecutors could bring treason charges in court, and Congress could — in theory — pursue impeachment only for “civil officers,” not typically for members ^{[5] [4]}. Sources do not present an example of a sitting member of Congress removed by impeachment for treason ^[5].

7. Competing perspectives and limits of the record

Scholars and institutions documented here agree on the constitutional text and the chamber expulsion power, but they diverge on contours: the Constitution Center and LegalClarity stress the political, discretionary nature of impeachment and the unclear scope of “high Crimes and Misdemeanors” ^{[9] [8]}, while historical summaries stress practice that members are expelled rather than impeached ^{[4] [3]}. Available sources do not assert a universally binding judicial rule barring impeachment of members in every conceivable circumstance; instead, the historical practice and interpretations show expulsion is the established remedy ^{[5] [4]}.

8. Bottom line for readers

If a member of Congress were credibly accused of treason, the practical constitutional path to immediate removal is expulsion by the member’s chamber via a two‑thirds vote ^[3]. Parallel criminal prosecution for treason could proceed in federal court, and impeachment-removal processes described in Article II pertain to civil officers rather than members of Congress per the sources cited ^{[5] [1]}.