The Twelfth Texas Legislature met from February 8, 1870 to December 2, 1871 in four sessions — provisional, called, regular, and adjourned.
The term Rump Senate is applied to the fifteen Radical Republican members of the Twelfth Texas Legislature, the term is a variation of "Rump legislature". This incident is the only time in history where senators were arrested under a "call of the Senate" and were then prohibited from rejoining their fellow senators and participating in Senate votes.
There had been a rash of incidents with Indian marauders and cattle thieves. One of the responses was on May 6, 1870, Senator Theodor Rudolph Hertzberg introduced a bill to reorganize the state militia. The bill included provisions for a unique "state guard" and for martial law. David Webster Flanagan who had for years been a staunch Radical Republican opposed the bill because of its clauses allowing Governor Edmund J. Davis to impose martial law. The cost was also the reason why some Republicans opposed the bill, but black Senator Matthew Gaines believed that racism was the reason for opposition, since many of the "state guard" would be black. On May 17, at a Republican caucus, Senators Bolivar Jackson Pridgen and E. L. Alford announced their opposition to the bill and were thrown out of the meeting.
Governor Davis announced that he would veto any bills which came across his desk before his militia legislation. Flanagan then offered to support the state militia bill if Governor Davis supported a railroad bill, but Davis publicly refused.
On June 16, 1870, Flanagan put forward a substitute militia bill without the martial law sections, but it failed to pass. Senator Mijamin Priest then publicly supported a bill which had passed the house, which would have suspended the writ of habeas corpus. In a public debate on June 17, Priest said that Texas was in a state of war with Indians and bandits, insisting that "a desperate disease requires a desperate remedy."
On June 21, Flanagan attempted to introduce his previous defeated bill as an alternative to the house bill which suspended the writ of habeas corpus. This motion failed. Flanagan then attempted to adjourn. According to a sworn statement by Parsons, Senator Fountain moved for a vote on the bill by roll. Thirteen Senators, Marmion Henry Bowers, Flanagan, Alford, E. Thomas Broughton, Amos Clark, David W. Cole, Ebenezer Lafayette Dohoney, James Postell Douglas, Andrew J. Evans, Henry Russell Latimer, Edward Bradford Pickett, William H. Pyle, and George R. Shannon, withdrew from the chamber to prevent the presence of a quorum and to prevent passage of the bill, to a nearby Capitol committee room.