In what election experts and observers described as a disturbing moment during the first presidential debate on Tuesday night, President Donald Trump urged his supporters to "watch" polling places as he sowed doubt in the integrity of the election.
Speaking about an incident in Philadelphia earlier that day, where people claiming to be poll watchers were turned away from satellite elections offices, Trump said, "They were thrown out. They weren't allowed to watch.
"You know why?" he said. "Because bad things happen in Philadelphia."
Poll watchers have been part of elections in the US — and around the world — for a long time, but despite Trump's request for supporters to show up at the polls, people can't just go to a polling place to check out what's going on there. There's a process — and rules on how to do it — and it varies by state.
Some states don't allow observers at the polls, while others permit poll watchers to observe nearly every stage of the election process, from the testing of voting machines to the counting of ballots.
In Pennsylvania, for example, where the incident Trump referred to occurred, people can only observe voting at traditional polling locations on Election Day. Poll watchers are not permitted to observe satellite elections offices in Philadelphia, and the city has not yet certified any election observers for the general election, according to elections officials.
On Thursday, the Trump campaign filed a lawsuit against the Philadelphia County Board of Elections for not allowing the uncertified poll watchers to monitor voting at the satellite offices.
"We can't just have people ... going to places they think are going to be hot spots for election fraud and showing up there without any accreditation or authorization," said Nina Jankowicz, an international election observer and disinformation fellow at the Woodrow Wilson Center, a nonpartisan think tank in Washington, DC. "I worry that with that open invitation for his supporters to come and 'protect' the election without all of that background information things could get very ugly very quickly."
In light of the president's comments, BuzzFeed News reached out to experts to help explain the purpose poll watchers serve, who gets to be a poll watcher, and what they actually can and can't do at the polls.
What are poll watchers and what do they do?
Poll watchers, or elections observers, are typically appointed by parties, campaigns, or nonpartisan groups to literally observe various parts of the election process, including the casting of ballots at polling places and early voting sites, the tabulation of ballots at government elections offices, and recounts.
The whole practice of poll watching is an exercise in building confidence in the integrity of elections.
For observers who are sent to the polls by a party or campaign, the main objective of poll watching is to make sure that their party or candidate has a fair chance at winning the election by ensuring proper procedures are followed. They also track turnout, but aside from notifying election officials or party officials of any issues they see, they are not allowed to intervene in or interfere with the process.
"The observer just observes and reports on what they see," Jankowicz told BuzzFeed News. "The election observers aren't there to change any outcome. They are there to document what they see."
What aren't they allowed to do?
Poll watchers cannot campaign inside polling locations, and they cannot wear or provide any campaign material. Some states expressly forbid election observers from taking photos and sitting in certain places.
Poll watchers are also — and this is VERY important — not allowed to intimidate voters by any means, which is punishable by state and federal laws.
"It's illegal in every state to harass or intimidate a voter away from voting," said Suzanne Almeida, interim executive director of Common Cause Pennsylvania. "There are specific rules in the election code about not standing in the way of a voter and their franchise, and so poll watchers can't do that either."
While the rules differ from state to state, they are generally not allowed to interact with voters and state laws usually dictate where they can observe the process at the polling place — if they're allowed there at all.
For example, poll watchers can't walk by people waiting in line to vote and say, "You know it's a felony to vote if you're not registered," said Bob Brandon, president and CEO of the Fair Elections Center.
"That would be totally inappropriate," Brandon told BuzzFeed News.
Who can be a poll watcher?
Partisan poll watchers are usually required to be registered voters, but states have different rules on whether they need to be registered in the specific precinct or county where they are observing the polls.
Most states require poll watchers to be appointed by a partisan or nonpartisan group and certified or authorized by local officials ahead of time. Some cap or limit the number of observers in a given polling place.
In Wisconsin, anyone except a candidate can show up at a polling place on Election Day to be an official election observer. They just have to notify on the on-site election officials they are there to observe, follow their directions, present a photo ID, sign an observer log, and wear an observer badge.
Training is required in some states but that isn't the case everywhere.
"Nothing is universal," said Franita Tolson, a vice dean and professor at the USC Gould School of Law and CNN election law analyst.
Despite it being against the law, political parties in the past trained poll watchers to intimidate voters as a means of voter suppression.
In the early 1980s, the Democratic National Committee sued the Republican National Committee and the New Jersey Republican State Committee, alleging that the party "under the guise of ballot security" harassed and intimidated Black and Latino voters using armed poll watchers "with the effect of discouraging these voters from casting their ballots."
As a result, the parties entered into a consent decree that prohibited Republicans from using the tactics. That decree recently expired after efforts to renew it failed.
At a time when armed groups of civilians have been showing up at Black Lives Matter protests to purportedly protect property, the Trump campaign's efforts to recruit more people to become poll watchers have raised concerns that the effort is yet another operation aimed at intimidating voters.
Last month, officials in Fairfax, Virginia, had to escort voters past a group of Trump supporters who had gathered outside an early voting site chanting "four more years" and waving campaign flags.
In a recent campaign ad, the president's son Donald Trump Jr. called for an “army” of “able-bodied” men and women for his dad's "election security operation." “We need you to help us watch them," he said.
"I hope that once people sign up for that, they’re going through proper training to go be a poll observer, but what [President] Trump called for [at Tuesday's debate] wasn't that sort of organized like, Hey I want you to be a poll watcher and to adhere by all of the restrictions that might exist in your state," Jankowicz said. "Instead, it was, Just show up and watch the polls because the election is going to be rigged and we need you to protect the election for me, and that's really disturbing."
In a statement emailed to BuzzFeed News, Thea McDonald, a spokesperson for the Trump campaign, said their poll watchers will be trained "to ensure all rules are applied equally, all valid ballots are counted, and all Democrat rule breaking is called out."
"And if fouls are called, the Trump Campaign will go to court to enforce the laws, as rightfully written by state legislatures, to protect every voter’s right to vote," McDonald said. "President Trump and his team will be ready to make sure polls are run correctly, securely, and transparently as we work to deliver the free and fair election Americans deserve."
Kadia Goba contributed reporting.