Early voters use electronic ballot casting machines at the Franklin County Board of Elections on Nov. 7 in Columbus, Ohio. (John Minchillo/Associated Press)

On the eve of Election Day, civil rights groups and local election officials were reminding voters of the state and federal laws protecting against voter intimidation and advising them where to go if they experience threats or harassment at the polls.

Anyone trying to keep a person from voting or to get them to vote a certain way constitutes voter intimidation, according to Election Protection, a nonpartisan voting rights coalition.

Voter intimidation is prohibited under federal law, which states that “no person . . . shall intimidate, threaten, coerce . . . any other person for the purpose of interfering with the right of [that] person to vote or to vote as he may choose.”

The American Civil Liberties Union says that one example of such intimidation is aggressively questioning a voter about his or her citizenship, criminal record or other qualifications to vote. Other examples include falsely presenting oneself as an elections official and spreading false information about voter requirements, such as the need to present a certain type of photo identification when there is no such requirement, according to the ACLU.

People wait in a long line to vote in a primary election in Chandler, Ariz. (David Kadlubowski/Associated Press)

Shouting and abusive language is also considered intimidation, according to the Brennan Center for Justice. If a voter is being followed and photographed or has his license plate numbers recorded, that also qualifies as intimidation, as does baseless or discriminatory challenges to one’s eligibility to vote and the brandishing of weapons in front of a voter.

Ten states have laws about guns at election polling places. Six generally prevent guns in polling places (Arizona, California, Florida, Georgia, Louisiana and Texas). Four others prohibit concealed-carry guns in polling places (Mississippi, Missouri, Nebraska and South Carolina).

In Arizona, the secretary of state’s office released a long list last week describing illegal intimidating conduct, including blocking the entrance to a polling place, disrupting voting lines, raising one’s voice or taunting a voter or poll worker, or photographing or filming voters in a harassing manner. The state also counts any aggressive display of weapons; using threatening, insulting or offensive language to a voter or poll worker; intentionally disseminating false information at a polling place; and directly confronting or asking voters for “documentation” or other questions that only poll workers should perform.

Voting rights advocates are more worried about voter intimidation this election because Republican presidential nominee Donald Trump is encouraging his supporters to sign up on his website to be a “Trump election observer” and to “watch” the polls.

Donald Trump has called for his supporters to "watch" the polls in some cities. But claims of election rigging didn't begin with Trump's candidacy. (Victoria Walker/The Washington Post)

“And when I say ‘watch,’ you know what I’m talking about,” Trump said at a rally in August. “Right? You know what I’m talking about. I think you’ve got to go out and you’ve got to watch.” Trump specifically encouraged supporters in Pennsylvania to be vigilant for voter fraud, saying that “cheating” is the only thing that could stop him from defeating Democratic nominee Hillary Clinton in that battleground state.

These states have new voting laws. Find out how to vote in your state.

In Pennsylvania, state officials concerned about potential intimidation or discrimination sent advisories to voters and county election officials.

“Discouraging anyone from having their voice be heard in the electoral process — whether by intimidation, suppression or deception — is absolutely unacceptable and wrong,” Pennsylvania Secretary of State Pedro A. Cortés said last month. “Any attempts to disrupt or interfere with voting by Pennsylvanians should and will be investigated and prosecuted by law enforcement.”

Individuals who intimidate voters can be fined up to $5,000 and face up to two years in prison, according to Pennsylvania law. Under federal law, a person who conspires to interfere with a person’s right to vote can face up to 10 years in prison.

A controversial case of voter intimidation allegations occurred in a Philadelphia neighborhood in 2008 when two New Black Panther Party members stood outside a polling place dressed in black paramilitary uniforms. One of them was seen on an amateur video, carrying a black nightstick. The incident led to a lawsuit, but the Justice Department eventually dismissed it.

Those who experience intimidation at the polls can contact state or federal officials. Voters can call the Justice Department Voting Rights Hotline at 800-253-3931; TTY line at 877-267-8971 or email the Justice Department Civil Rights Division at voting.section@usdoj.gov.

Voters also can call the Election Protection hotline led by the Lawyers’ Committee for Civil Rights Under Law (866-OUR-VOTE), the hotline led by the National Association of Latino Elected and Appointed Officials Education Fund (888-Ve-Y-Vota), or the hotline led by APIAVote and Asian Americans Advancing Justice (888-API-VOTE). The Arab American Institute Yalla Vote Hotline is 844-418-1682. In addition, voters can report intimidation to county poll workers, the county clerk, elections officials, local and state officials, or the state board of elections.

In some states, police officers are allowed inside polling places. Voters can report harassment and intimidation incidents to the police, who are subject to voter intimidation laws.