The Act authorized the President to deploy federal troops to counter the Klan and to suspend the writ of habeas corpus to make arrests without charge.

After the act's passage, the president had the power for the first time to both suppress state disorders on his own initiative and to suspend the writ of habeas corpus.

Grant did not hesitate to use this authority on numerous occasions during his presidency, and as a result the KKK was completely dismantled (ending the "first Klan" era) and did not resurface in any meaningful way until the beginning of the 20th century.

In response to political violence by the Ku Klux Klan and others during the Reconstruction era following the American Civil War, Congress passed three Enforcement Acts giving the federal government broader powers to guarantee citizens' constitutional rights.

The third of these acts, enacted in April 1871, gave the president the power to imprison people without a trial (known as suspending the writ of habeas corpus) and to use the federal military on domestic soil to enforce constitutional rights, among other measures.

[7] In January 1871, Republican Senator John Scott of Pennsylvania convened a congressional committee to hear testimony from witnesses of Klan atrocities.

In February, Republican Congressman Benjamin Franklin Butler of Massachusetts introduced his anti-Klan bill, intended to enforce both the Fourteenth Amendment and the Civil Rights Act of 1866.

[8] After the Civil War, President Ulysses S. Grant conducted an aggressive—and ultimately successful—campaign against the Ku Klux Klan and its offshoots (such as the Knights of the White Camellia) from the 1860s to the 1870s.

After the end of the Grant Administration, and the dismantling of Reconstruction under Rutherford B. Hayes, enforcement of the Act fell into disuse and few cases were brought under the statute for almost a hundred years.

[11] In February 2021, the NAACP and law firm Cohen Milstein filed another lawsuit invoking the act on behalf of U.S. Representative Bennie Thompson.

[17][18] Following lawsuits filed by Thompson and Swalwell, the Lawyers' Committee for Civil Rights Under Law filed its complaint on behalf of seven officers working with United States Capitol Police accusing Trump, Roger Stone, Proud Boys, Stop the Steal, Oath Keepers and other persons who conspired to attack the Capitol under the same act and the D.C. Bias-Related Crimes Act.

[19] On February 2, 2022, Vindman sued several Trump allies, alleging that they intimidated and retaliated against him while he testified in Congress, and thereby violated the Ku Klux Klan Act of 1871.

[24] Section 1979 of the Revised Statutes now reads:[25] Every person who under color of any statute, ordinance, regulation, custom, or usage, of any State or Territory or the District of Columbia, subjects, or causes to be subjected, any citizen of the United States or other person within the jurisdiction thereof to the deprivation of any rights, privileges, or immunities secured by the Constitution and laws, shall be liable to the party injured in an action at law, Suit in equity, or other proper proceeding for redress, except that in any action brought against a judicial officer for an act or omission taken in such officer's judicial capacity, injunctive relief shall not be granted unless a declaratory decree was violated or declaratory relief was unavailable.

"[26][27] A §1983 claim requires according to the United States Supreme Court in Adickes v. S. H. Kress & Co. (1970) two elements for recovery: (1) the plaintiff must prove that the defendant has deprived him of a right secured by the, "constitution and laws," of the US, and (2) the plaintiff must show that the defendant deprived him of this constitutional right 'under color of any statute, ordinance, regulation, custom, or usage, of any State or Territory' (under color of law).

Section 1985 authorizes lawsuits against people who conspire to commit certain prohibited acts, such as interfering with government, obstructing justice, or depriving a person of equal protection under the law.

[36] In addition, Section 1985(3) contains the "support-or-advocacy clauses", which cover conspiracies to harm citizens because of their support or advocacy for a federal candidate for public office.

[44] Although some provisions were ruled unconstitutional in 1883,[45] the 1870 Force Act and the 1871 Civil Rights Act have been invoked in later civil rights conflicts, including the 1964 murders of Chaney, Goodman, and Schwerner; the 1965 murder of Viola Liuzzo; and in Bray v. Alexandria Women's Health Clinic, 506 U.S. 263 (1993), in which the court ruled that "The first clause of 1985(3) does not provide a federal cause of action against persons obstructing access to abortion clinics."

The rise of the Black Lives Matter movement along with smart phone video cameras have made Section 1983 lawsuits easier to obtain because of technological advances, including bodycams worn by law enforcement.

[49] On February 16, 2021, the Act was asserted in an action[50] in the District Court, D.C., by Rep. Bennie G. Thompson (D, MS2), chair of the House Homeland Security Committee (in his personal capacity) against former President Donald Trump (in his personal capacity), Trump's attorney Rudolph Giuliani and (far-right "militia" groups) Proud Boys and Oath Keepers.