JUST A FEW short weeks before Election Day 2016, a meme began to circulate claiming that Hillary Clinton supporters in Pennsylvania, an electoral vote-rich swing state, could vote from the comfort of their homes by tweeting the words “Hillary” and “#PresidentialElection” between 7 AM and 9 PM on November 8. Although 22 states allow some form of Internet-based ballot-casting, Pennsylvania is not one of them. This online voting claim was a scam , and it was quickly debunked by Snopes .

Unfortunately, the online voting meme isn’t the only election scam we’ve seen in recent years. Like other, less timely hoaxes, election scams are generally intended to fleece vulnerable people out of their money. Fundraising calls from fake PACs and political surveys that offer too-good-to-be-true prizes are among the most frequent election scams, and, since political organizations are exempt from Do Not Call Registry regulations, it can be difficult for some people to tell the difference between a legitimate call and a fake one.

In one scam, callers tell voters that they’ll have to re-register if they did not cast a ballot in the last election, because their names were stricken from the record due to inactivity. That’s an out-and-out lie, no matter where you are, but it serves two purposes: to steal sensitive personal information from those who fall for it, and to spread a rumor that many people won’t be eligible to vote in this election .

More and more frequently, election scams appear to be designed to keep people from voting at all. Similar to the online voting scam is the fraudulent claim that voters may cast their ballots by sending an email, making a phone call, texting the name of a candidate, or visiting a fake website on Election Day.*

This is not the first presidential election to feature election scams designed to keep voters from heading out to their polling locations. Democratic voters in general, and people of color in particular, are popular targets.

In 2012, Maricopa County, Arizona — home of avowed racist Sheriff Joe Arpaio — sent out bilingual voter information cards that gave the date of the general election as November 8 on its Spanish-language side. On the English-language face, the cards featured the correct date: November 6. Although county officials tried to undo the misinformative damage that had been done,  TIME reported that “[t]he registration card debacle w[ould] likely only compound an already strained relationship between county authorities and Latino residents.”

What happened in Maricopa was strikingly similar to a 2008 incident in Virginia, in which Democrats were given flyers featuring the wrong date for Election Day. That same year, students at George Mason University received election-themed emails with the same, incorrect date listed as the day of the general election, and Drexel University students were told that undercover police officers would be patrolling polling locations to sniff out individuals with outstanding warrants or unpaid fines.

Threatening voters with police action is not uncommon. In 2004, people of color in Milwaukee received flyers from a fake organization, the “Milwaukee Black Voters League,” telling them that they could not vote in the general election if they had cast any other votes during the year, that minor infractions made them ineligible to vote, and that they were disqualified from voting if any of their relatives had committed a crime.  Mother Jones  reports that “menacing billboards” declaring “VOTER FRAUD IS A FELONY!” cropped up in minority neighborhoods in swing states in 2012, obviously intended to deter voters who were unsure of their eligibility from turning out to vote.

In 2016, Trump’s repeated warnings against nonexistent voter fraud have helped to mobilize an army of poll watchers, bent on intimidating Democratic voters at precincts around the country. Evidence that the Republican National Committee might be  “supporting and enabling [his] efforts … to intimidate and discourage minority voters from voting”  prompted the Democratic National Committee to file suit against the GOP for violating a 35-year-old court-imposed limitation on election activities.

The judgment that the RNC may have violated was handed down following a 1981 gubernatorial election in NJ, in which GOP-ordained observers, many of whom were off-duty police, physically restrained poll workers and impeded non-white voters to prevent them from casting their ballots. To be perfectly honest, it sounds a lot like what we’ll run into next week, when citizens turn out to elect the next President of the United States.

Whether voter intimidation fits your definition of an election scam or not, you should be aware of it and other attempts to prevent citizens from exercising their constitutional right to vote. Spread the word, in this and future elections, to keep your family and friends informed of their rights at the polls, and remember what you can do if your vote is compromised .

*Note: You can begin the voter registration process via text message , but no states allow you to vote using your phone.