Republicans frustrated by Roy Moore’s insistence on staying in the race for the U.S. Senate in Alabama despite allegations of sexual misconduct seem to have settled on a strategy. As articulated by Sen. Cory Gardner (R-Colo.), chairman of the National Republican Senatorial Committee, the idea would be to allow Moore to take his seat in the Senate, should he win next month’s general election, and then quickly begin the process to expel him from the body. (The Senate probably wouldn’t have any choice but to seat Moore, thanks to a 1969 Supreme Court decision.)

That process, in short, goes like this. (In long: Read this.) The Senate Ethics Committee conducts an investigation. If it finds grounds to expel him, the Senate can hold a vote to do so. If two-thirds choose to expel him, he’s out. Republicans control the Senate, but others already seem amenable to Gardner’s plan.

Nothing about their doing so would be normal. The Senate’s historian indicates that only about 30 senators have faced expulsion proceedings, most of which followed extensive tenures in the body. Only 15 were expelled, and 14 of those expulsions were of senators found to be sympathetic to the Confederacy during the Civil War.

(One, John Breckinridge, was a general in the Confederate Army. Another, Jesse Bright, was expelled after a friend was found to be carrying a letter from him to Jefferson Davis, president of the Confederacy. “He visits your capital mainly to dispose of what he regards a great improvement in fire-arms,” the letter read in part.)

More details on the expulsion investigations are below.

Such an effort would not be a sure thing, even setting aside the two-thirds vote count. Because these proceedings are rare, most seem to get mired in questions about the boundaries of the Senate’s authority. That, and several particular examples that mirror Moore’s situation, might suggest that Gardner’s plan would be more difficult than it seems.

Consider William Roach, about whom questions were raised in 1893. The allegation against Roach was that he had embezzled money when serving as a bank teller before being elected to the Senate. The Senate declined to investigate.

“After extensive deliberation,” the Senate historian wrote, “the Senate took no action, assuring that it lacked jurisdiction over members’ behavior before their election to the Senate. The alleged embezzlement had occurred 13 years earlier.” (The historian had no dates for Roach’s or Burton Wheeler’s allegations.)

Consider, too, William Langer. Langer was accused of corruption in 1941, with residents of his state seeking to block him from taking office. The Senate historian describes the fierce debate over the charges.

[Senators] were particularly concerned about the danger of establishing the precedent that the Senate could be used by a member’s political opponents to overturn the will of a state’s citizens as expressed at the polls. Referring to the majority report, the authors of the minority report, Ellison D. Smith (D-SC) and Abe Murdock (D-UT), warned the Senate, “We cannot think of a better illustration of the danger of being swept away by a barrage of slander.” Tom Connally (D-TX) concurred in the conclusion that there was insufficient evidence to warrant expelling or excluding Langer.

A majority of the Senate voted to allow Langer to hold his seat. (He’d already been sworn in as the debate raged.)

Both of those precedents might be heartening to Moore, who is accused of actions that occurred more than 30 years ago. Should he win office, an effort to expel him is not a sure thing.

More-recent senators have resigned rather than face the judgment of their peers. Moore so far seems disinclined to take that step, and his history in elected office — twice being censured while serving as chief justice of the Alabama Supreme Court — similarly suggests a willingness to see fights through to the end.

Of course, there are also politics at play. Republicans worried about 2018 may be more willing to oust Moore than senators were in 1893 or 1941. The concern that arose during the Langer debate — if accusations of improper action before election should be grounds for ouster — will still loom. But 2018 may be looming larger.

Past efforts to expel senators

William Blount (R-Tenn.), 1797.
Tried to incite a rebellion to return Florida and Louisiana to Britain to make money. Result: Expelled.
John Smith (R-Ohio), 1807.
Allegedly aiding Aaron Burr in a revolt. Result: Not expelled.
James Mason (D-Va.), 1861.
Support for the Confederacy. Result: Expelled.
Robert Hunter (D-Va.), 1861.
Support for the Confederacy. Result: Expelled.
Thomas Clingman (D-N.C.), 1861.
Support for the Confederacy. Result: Expelled.
Thomas Bragg (D-N.C.), 1861.
Support for the Confederacy. Result: Expelled.
James Chesnut (D-S.C.), 1861.
Support for the Confederacy. Result: Expelled.
Alfred Nicholson (D-Tenn.), 1861.
Support for the Confederacy. Result: Expelled.
William Sebastian (D-Ark.), 1861.
Support for the Confederacy. Result: Expelled.
Charles Mitchel (D-Ark.), 1861.
Support for the Confederacy. Result: Expelled.
John Hemphill (D-Tex.), 1861.
Support for the Confederacy. Result: Expelled.
Louis Wigfall (D-Tex.), 1861.
Support for the Confederacy. Result: Expelled.
John Breckinridge (D-Ky.), 1861.
Serving as a Confederate general. Result: Expelled.
Lazarus Powell (D-Ky.), 1862.
Support for the Confederacy. Result: Not expelled.
Waldo Johnson (D-Mo.), 1862.
Support for the Confederacy. Result: Expelled.
Trusten Polk (D-Mo.), 1862.
Support for the Confederacy. Result: Expelled.
Jesse Bright (D-Ind.), 1862.
Support for the Confederacy. Result: Expelled.
James Simmons (R-R.I.), 1862.
Corruption. Result: Resigned.
James Patterson (R-N.H.), 1873.
Fraud related to the transcontinental railroad. Result: Not expelled.
William Roach (D-N.D.), 1893.
Embezzlement. Result: Not expelled.
Joseph Burton (R-Kan.), 1906.
Corruption. Result: Resigned.
Reed Smoot (R-Utah), 1907.
Being a Mormon. Seriously. You can read more about this at the Senate’s site. Result: Not expelled.
Robert LaFollette (R-Wis.), 1919.
Sedition. Result: Not expelled.
Truman Newberry (R-Mich.), 1922.
Campaign finance violations. Result: Not expelled.
Burton Wheeler (D-Mont.), 1924.
Conflict of interest. Result: Not expelled.
John Overton (D-La.), 1934.
Election fraud. Result: Not expelled.
Huey Long (D-La.), 1934.
Election fraud. Result: Not expelled.
William Langer (R-N.D.), 1942.
Corruption. Result: Not expelled.
Harrison Williams Jr. (D-N.J.), 1982.
Corruption. Result: Resigned.
Robert Packwood (R-Ore.), 1995.
Abuse of power. Result: Resigned.
John Ensign (R-Nev.), 2011.
Corruption. Result: Resigned.