As a response to attempts on the part of some groups in the South to undermine the Republican Party through violence, Congress passed a series of Force Acts designed to protect people's right to vote. The United States Army, which still had troops stationed in the South, was one institution given the responsibility of enforcing these laws. The Acts were upheld by the Supreme Court in 1883 on the basis of the 15^th Amendment to the Constitution.

Excerpts follow:

To enforce the Right of Citizens of the United States to vote in the several States of this Union, and for other Purposes. Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That all citizens of the United States who are or shall be otherwise qualified by law to vote at any election by the people in any State, Territory, district, county, city, parish, township, school district, municipality, or other territorial subdivision, shall be entitled and allowed to vote at all such elections, without distinction of race, color, or previous condition of servitude; any constitution, law, custom, usage, or regulation of any State or Territory, or by or under its authority, to the contrary notwithstanding.  ...

Sec. 4. And be it further enacted, That if any person, by force, bribery, threats, intimidation, or other unlawful means, shall hinder, delay, prevent, or obstruct, or shall combine and confederate with others to hinder, delay, prevent, or obstruct, any citizen from doing any act required to be done to qualify him to vote or from voting at any election as aforesaid, such person shall for every such offence forfeit and pay the sum of five hundred dollars to the person aggrieved thereby, to be recovered by an action on the case, with full costs, and such allowance for counsel fees as the court shall deem just, and shall also for every such offence be guilty of a misdemeanor, and shall, on conviction thereof, be fined not less than five hundred dollars, or be imprisoned not less than one month and not more than one year, or both, at the discretion of the court.

Sec. 5. And be it further enacted, That if any person shall prevent, hinder, control, or intimidate, or shall attempt to prevent, hinder, control, or intimidate, any person from exercising or in exercising the right of suffrage, to whom the right of suffrage is secured or guaranteed by the fifteenth amendment to the Constitution of the United States, by means of bribery, threats, or threats of depriving such person of employment or occupation, or of ejecting such person from rented house, lands, or other property, or by threats of refusing to renew leases or contracts for labor, or by threats of violence to himself or family, such person so offending shall be deemed guilty of a misdemeanor, and shall, on conviction thereof, be fined not less than five hundred dollars, or be imprisoned not less than one month and not more than one year, or both, at the discretion of the court.

Sec. 6. And be it further enacted, That if two or more persons shall band or conspire together ... to violate any provision of this act, or to injure, oppress, threaten, or intimidate any citizen with intent to prevent or hinder his free exercise and enjoyment of any right or privilege granted or secured to him by the Constitution or laws of the United States, or because of his having exercised the same, such persons shall be held guilty of felony, and, on conviction thereof, shall be fined or imprisoned, or both, at the discretion of the court, -- the fine not to exceed five thousand dollars, and the imprisonment not to exceed ten years ...

Sec. 8. And be it further enacted, That the district courts of the United States, within their respective districts, shall have, exclusively of the courts of the several States, cognizance of all crimes and offences committed against the provisions of this act ...

Sec. 9. And be it further enacted, That the district attorneys, marshals, and deputy marshals of the United States, the commissioners appointed by the circuit and territorial courts of the United States, with powers of arresting, imprisoning, or bailing offenders against the laws of the United States, and every other officer who may be specially empowered by the President of the United States, shall be, and they are hereby, specially authorized and required, at the expense of the United States, to institute proceedings against all and every person who shall violate the provisions of this act, and cause him or them to be arrested and imprisoned, or bailed, as the case may be, for trial before such court of the United States or territorial court as has cognizance of the offense. ...

Sec. 10. And be it further enacted, That it shall be the duty of all marshals and deputy marshals to obey and execute all warrants and precepts issued under the provisions of this act, when to them directed; ...

Sec. 13. And be it further enacted, That is shall be lawful for the President of the United States to employ such part of the land or naval forces of the United States, or of the militia, as shall be necessary to aid in the execution of judicial process issued under this act. ...

Sec. 20. And be it further enacted, That if, at any registration of voters for an election for representative or delegate in the Congress of the United States, any person shall knowingly personate and register, or attempt to register, in the name of any other person ... or fraudulently register, or fraudulently attempt to register ... himself or any other person; or by force, threat, menace, intimidation, bribery, reward, or offer, or promise thereof, or other unlawful means, prevent or hinder any person having a lawful right to register from duly exercising such right ...  every such person shall be deemed guilty of a crime, and shall be liable to prosecution and punishment therefor, as provided in section nineteen of this act for persons guilty of any of the crimes therein specified ...

AN ACT To amend an Act approved May thirty-one, eighteen hundred and seventy, entitled "An Act to enforce the Rights of Citizens of the United States to vote in the several States of this Union, and for other Purposes."

Sec. 2. And be it further enacted, That whenever in any city or town having upward of twenty thousand inhabitants, there shall be two citizens thereof who, prior to any registration of voters for an election for representative or delegate in the Congress of the United States, or prior to any election at which a representative to delegate in Congress is to be voted for, shall make known, in writing, to the judge of the circuit court of the United States for the circuit wherein such city or town shall be, their desire to have said registration, or said election, or both, guarded and scrutinized, it shall be the duty of the said judge of the circuit court, within not less than ten days prior to said registration ... to open the said circuit court at the most convenient point in said circuit. And the said court, when so opened by said judge, shall proceed to appoint and commission ... two citizens, residents of said city or town, who shall be of different political parties, and able to read and write the English language, and who shall be known and designated as supervisors of election.

Sec. 4. And be it further enacted, That it shall be the duty of the supervisors of election ... to attend at all times and places when the names of registered voters may be marked for challenge, and to cause such names of registered as they shall deem proper to be so marked; to make, when required, the lists, or either of them, provided for in section thirteen of this act, and verify the same; and upon any occasion, and at any time when in attendance under the provisions of this act, to personally inspect and scrutinize such registry, and for purposes of identification to affix their or his signature to each and every page of the original list ... in such manner as will, in their or his judgment, detect and expose the improper or wrongful removal therefrom, or addition thereto, in any way, of any name or names.

Second Force Act of 1871

Sec. 2. That if two or more persons within any State or Territory of the United States shall conspire together to overthrow, or to put down, or to destroy by force the government of the United States, or to levy war against the United States, or to oppose by force the authority of the government of the United States, or by force, intimidation, or threat to prevent, hinder, or delay the execution of any law of the United States, or by force of seize, take, or possess any property of the United States contrary to the authority thereof, or by force, intimidation, or threat to prevent any person from accepting or holding any office or trust or place of confidence under the United States, or from discharging the duties thereof, or by force, intimidation, or threat to induce any office of the United States to leave any State, district, or place where his duties as such officer might lawfully be performed, or to injure him in his person or property on account of his lawful discharge of the duties of his office, or to injure his person while engaged in the lawful discharge of the duties of his office, or to injure his property so as to molest, interrupt, hinder, or impede him in the discharge of his official duty, or by force, intimidation, or threat to deter any party or witness in any court of the United States from attending such court, or from testifying in any matter pending in such court fully, freely, and truthfully, or to injure any such party or witness in his person or property on account of his having so attended or testified, or by force, intimidation, or threat to influence the verdict, presentment, or indictment, of any juror or grand juror in any court of the United States, or to injure such juror in his person or property on account of any verdict, presentment, or indictment lawfully assented to by him, or on account of his being or having been such juror, or shall conspire together, or go in disguise upon the public highway or upon the premises of another for the purpose, either directly or indirectly, of depriving any person or any class of persons of the equal protection of the laws, or of equal privileges of immunities under the laws, or for the purpose of preventing or hindering the constituted authorities of any State from giving or securing to all persons within such State the equal protection of the laws, or shall conspire together for the purpose of in any manner impeding, hindering, obstructing, or defeating the due course of justice in any State of Territory, with intent to deny to any citizen of the United States the due and equal protection of the laws, or to injure any person in his person or his property for lawfully enforcing the right of any person or class of persons to the equal protection of the laws, or by force, intimidation, or threat to prevent any citizen of the United States lawfully entitled to vote from giving his support or advocacy in a lawful manner towards or in favor of the election of any lawfully qualified person as an elector of President or Vice-President of the United States, or as a member of the Congress of the United States, or to injure any such citizen in his person or property on account of such support or advocacy, each and every person so offending shall be deemed guilty of a high crime, and, upon conviction thereof in any district or circuit court of the United States or district or supreme court of any Territory of the United States having jurisdiction of similar offenses, shall be punished by a fine not less than five hundred nor more than five thousand dollars, or by imprisonment, with or without hard labor, as the court may determine, for a period of not less than six months nor more than six years, as the court may determine, or by both such tine and imprisonment as the court shall determine. ...

Sec. 3. That in all cases where insurrection, domestic violence, unlawful combinations, or conspiracies in any State shall so obstruct or hinder the execution of the laws thereof, and of the United States, as to deprive any portion or class of the people of such State of any of the rights, privileges, or immunities, or protection, named in the Constitution and secured by this act, and the constituted authorities of such State shall either be unable to protect, or shall, from any cause, fail in or refuse protection of the people in such rights, such facts shall be deemed a denial by such State of the equal protection of the laws to which they are entitled under the Constitution of the United States; and in all such cases, or whenever any such insurrection, violence, unlawful combination, or conspiracy shall oppose or obstruct the laws of the United States or the due execution thereof, or impede or obstruct the due course of justice under the same, it shall be lawful: for the President, and it shall be his duty to take such measures, by the employment of the militia or the land and naval forces of the United States, or of either, or by other means, as he may deem necessary for the suppression of such insurrection, domestic violence, or combinations; and any person who shall be arrested under the provisions of this and the preceding section shall be delivered to the marshal of the proper district, to be dealt with according to law.