Described as a "fierce fanatic of the Republican Party,"[1] Mullins supported the initiatives of Governor William G. Brownlow in the state legislature, most notably leading efforts to ratify the Fourteenth Amendment.
[9][10] Mullins' opposition to secession put him at odds with Bedford County and Middle Tennessee in general, and he was compelled to flee in 1862.
Conservatives, led by Speaker of the House William Heiskell, generally sought a return to pre-Civil War conditions (though with slavery outlawed), while Radicals wanted to extend voting rights to African-Americans and punish former Confederates.
[14] In February 1866, a franchise bill was introduced in the legislature that would give Governor Brownlow the power to throw out the votes of any county in any election in which ex-Confederates were suspected of casting ballots.
Conservative legislators opposed the bill, but having little chance of stopping its passage, fled the capital in an attempt to prevent a quorum.
"[17] In July 1866, Brownlow called a special session of the General Assembly to consider the Fourteenth Amendment, which extended civil rights to African Americans.
After two of the quorum-busting legislators were arrested and confined to the House chamber, the radicals argued this constituted a quorum, and pushed through the vote in favor ratifying the amendment.
[19] Mullins was on the ballot for the 4th district congressional seat in 1865, but lost by a wide margin to Edmund Cooper, a state senator.
Determined to defeat Johnson's ally, Brownlow dispatched two state guard companies to the fourth district, and prevented a large number of previously-eligible voters from registering.
[24] During the late 1860s, Mullins became embroiled in a scandal when the Tennessee National Bank of Memphis, where the state's school fund had been deposited, failed.
[30] Mullins' support of black suffrage and other initiatives of the Radical Republicans made him a target of the burgeoning Ku Klux Klan.
While Mullins was campaigning for Congress in October 1870, a group of Klansmen attacked his farm, burning his barn, stables, and mills.