If he isn't elected, presidential candidate Donald Trump suggests it will be because of a conspiracy against him.
But Richard Hasen says that's pretty much impossible.
He's an expert on election law at UC-Irvine, and gave Take Two a breakdown the many reasons why.
There's no such thing as "one election"
To put a fix into a national election requires more than one plan. The counting process is different across many states and many counties – it would take thousands of plans.
"We run our election in something like 14,000 electoral jurisdictions," he says, and each has their own rules, machines and methods. The coordination it would take to infiltrate and break those systems is unheard of.
"That decentralization does have the benefit that there's no single entity counting the votes that could manipulating it behind the scenes," Hasen adds.
You can't hack vote counting machines
"We're not talking about hacking into systems that count votes," says Hasen because those typically are not connected to the internet. There are many different devices that tabulate ballots as they are cast, and even then they create a paper trail that cannot be changed.
So if a hacker wanted to infiltrate those machines, s/he would have to figure out which device a community uses, create a program to infect it, gain physical access to that machine to install the program and then destroy that paper trail. Then repeat that across thousands of polling places across the country.
"There's no evidence that there's some attempt to change the code on those places that use electronic voting machines," he says.
Neither is there one corruptible database that collects all the country's votes in the presidential race.
"There's not a single repository of vote counts where the Russians or anyone else can go in and change things," says Hasen.
Voter fraud has not affected the outcome of any U.S. election in decades
People who say voter fraud exists suspect it's done by those who cast multiple ballots for the same candidate, or steal the identity of someone else and vote in their name.
Hasen researched elections back to 1980 to find instances where that ended up flipping the outcome.
"I couldn't find a single example," he says. "It's a dumb way to try and steal an election."
Hasen says that tactic would require a lot of people in an area doing the same thing to stuff a ballot box. Even then, they would also have to keep it quiet.
"To do that on a large enough scale to affect a presidential election," says Hasen, "there's just no way something like that could happen on that scale in this country with everybody watching."
There are many eyes watching the vote count
Election observers – Democratic, Republican and non-partisan – volunteer to oversee the vote counting process.
"It's not done in a backroom," says Hasen. "Election officials want their work to be seen and they want it to be a public process."
You can sign up to be a poll watcher, too.
"You get some training, in most places. You don't just show up," he says. "You can work with a political party or a non-partisan group that looks to protect the vote."
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