U.S. President Donald Trump lied about a wide variety of topics -- including health care, the economy and the coronavirus pandemic -- during Tuesday's presidential debate. But he was especially dishonest on the subject of voting by mail.

Almost every single claim Trump made during the debate segment about the integrity of the election was inaccurate in whole or in part.

His Tuesday performance was just the latest component of a systematic, months-long disinformation campaign he has waged to try to undermine confidence in mail-in voting. Let's go through 11 of his Tuesday claims item by item:

MAIL VOTING AND FRAUD

Trump said, "As far as the ballots are concerned, it's a disaster." He went on to say that "a solicited ballot" is "OK" but an "unsolicited" ballot is not. And he added, later, that "It's a rigged election."

Facts First: Trump is lying. The election is not rigged. Fraud is exceedingly rare in U.S. elections -- whether with in-person voting, mail voting in states where voters have to request ballots or mail voting in states where all eligible registered voters are sent ballots without having to make requests.

Voters in nine states and the District of Columbia are being sent mail ballots without needing to request them. However, five of those states -- Colorado, Oregon, Utah, Hawaii and Washington -- have held their elections primarily by mail since before the pandemic, and there has not been any significant incidence of fraud.

Since Trump is alleging that Democrats are using mail voting to try to rig the election, it's worth noting that Utah is governed by Republicans; Vermont has a Republican governor, though a Democratic-controlled Legislature; and the top election officials in Nevada, Oregon and Washington are all Republicans. It's also worth noting that Republican election officials around the country have emphasized that mail voting is fair and secure.

A DEMOCRATIC PRIMARY IN NEW YORK

After Biden said nobody has established that mail voting is a fraudulent process, Trump replied, "It's already been established. Take a look at Carolyn Maloney's race in Manhattan."

Facts First: This is false. There has been no evidence to date of fraud in this primary in New York's 12th District. There was a legal dispute about the fact that a large number of ballots were rejected for non-fraud reasons. And while the ballot-counting was slow because the state has had administrative problems -- ranging from insufficient staffing to outdated technology -- in trying to count a much larger than usual number of absentee votes, a slow count is not evidence of anything nefarious.

The candidate Maloney defeated, Suraj Patel, tweeted Tuesday night that "Trump lied about what happened here," saying that the issue in the race was "disenfranchisement" of voters whose ballots had been rejected, "not voter fraud."

A MAILMAN IN WEST VIRGINIA

Trump said, "Take a look at West Virginia, mailmen selling the ballots. They're being sold."

Facts First: This is false in three ways. There is one known recent instance of attempted election fraud in West Virginia by a postal carrier -- a single postal carrier who altered applications for absentee ballots during the 2020 primaries. So it wasn't "mailmen" plural, it didn't involve "selling" anything and it was applications rather than ballots themselves.

According to the Department of Justice, Thomas Cooper changed the party affiliation on five absentee ballot applications from Democratic to Republican, and also changed parts of three other applications.

Cooper, who had claimed that he was joking, pleaded guilty to one count of attempted election fraud and one count of "injury to the mail," according to the Department of Justice.

West Virginia Secretary of State Mac Warner, a Republican, issued a statement Wednesday saying that the incident was a "unique circumstance" that involved applications, "not ballots." He said: "The timely prosecution of election fraud in the 2020 Primary election cycle in West Virginia shows that we take election fraud seriously, that the system we have in place works well. Voters should be confident that this election will be safe, secure, and fair."

THE SITUATION IN PHILADELPHIA

Trump said, "As you know, today there was a big problem. In Philadelphia, they went in to watch. They're called poll watchers, a very safe, very nice thing. They were thrown out. They weren't allowed to watch. You know why? Because bad things happen in Philadelphia. Bad things."

Facts First: Trump's version of what happened in Philadelphia is highly misleading; contrary to his suggestion, nothing nefarious happened there. Some pro-Trump poll watchers were turned away from voting sites -- but local officials said this was because poll watchers, whether Republican or Democratic, are allowed under state law to observe voting only at in-person sites on election day in November. Independent election experts pointed out that official poll watchers for November haven't even been named and certified yet in the state.

PEOPLE BEING SENT TWO BALLOTS

Trump said of mail ballots: "They're being sent all over the place. They sent two in a Democrat area -- they sent out a thousand ballots. Everybody got two ballots. This is going to be a fraud like you've never seen."

Facts First: There was an error in Democratic-leaning Fairfax County, Virginia, that resulted in an estimated 1,000 voters being sent two ballots, but this does not mean there will be any fraud. Fairfax County officials have explained that when anyone returns a ballot with their vote, the fact that they have done so is marked in their voter record -- so they cannot vote twice.

REJECTED BALLOTS IN THE 2016 ELECTION

Trump said, "I read today where at least 1% of the ballots for 2016 were invalidated. They take 'em. 'We don't like 'em. We don't like 'em.' They throw them out, left and right."

Facts First: Trump's "1%" number was correct, but he was inaccurately suggesting this number is evidence of something nefarious happening. According to the federal government's Election Assistance Commission, "The most common reasons for rejection in 2016 were missing the deadline, the signature on the ballot not matching the signature on the state's records, and the ballot not having a signature."

It's theoretically possible that there could be fraud involved in some of the cases of nonmatching or missing signatures, but there's no proof of even that.

MORE ON BALLOTS

Trump vaguely urged people to look at what is happening in various places in the U.S., then said, "They're not losing 2%, 1%, which by the way is too much. An election could be won or lost with that. They're losing 30 and 40%. It's a fraud, and it's a shame."

Facts First: Trump was vague here about what he meant by "losing" and "it's a fraud," but there are no recent examples of 30% or 40% of ballots in an election getting lost or being deemed fraudulent.

Trump has often cited a case of alleged fraud in a city council race in Paterson, New Jersey, over which four people face charges. But the percentage of possible fraudulent ballots even in that election does not appear to be nearly as high 30% or 40%. According to attorney Scott Salmon, who represents the incumbent city council member who is the alleged victim of the fraud, about 900 ballots, roughly 5% of the total vote, were potentially fraudulent.

CREEKS AND RIVERS

Trump said of ballots: "They found 'em in creeks." He also said, "They're being dumped in rivers."

Facts First: We could not find any examples of 2020 ballots being found in "creeks" or "dumped in rivers." Trump might have been referring to a Wisconsin case in which three trays of mail that were supposed to be headed to the local post office were found on the side of the road and in a ditch off of Highway 96 in Outagamie County, Wisconsin, according to the Outagamie County Sheriff's Office, local TV station WBAY reported. Some of the mail included absentee ballots, the sheriff's office said.

Wisconsin's chief election official, Meagan Wolfe, said the USPS was investigating the situation. She told reporters this month that if absentee ballots were lost, they could be traced with intelligent mail bar codes placed on absentee ballot mail to ensure all ballots are tracked.

AN INCIDENT IN PENNSYLVANIA

Trump said: "Number two, they cheat. They cheat. Hey, they found ballots in a wastepaper basket three days ago, and they all had the name military ballots -- there were military -- they all had the name Trump on 'em."

Facts First: It's true that there was an incident with a small number of discarded ballots in one county in Pennsylvania, but what happened is not evidence of cheating. Also, Trump was wrong that all of these ballots were cast for him. There were nine discarded ballots; seven were Trump votes, according to an unusual statement from the Department of Justice, while the recipient of the other two votes is not known.

According to federal and local authorities, an election worker improperly threw out nine military ballots in Luzerne County. The Justice Department initially said all nine of the ballots were marked for Trump, then deleted its initial statement and issued a new one saying only seven were Trump votes. Local officials said they would try to reach the affected voters and fix the ballots.

Luzerne County officials said that the incident was caused by a "temporary seasonal independent contractor" who "incorrectly discarded (the ballots) into the office trash" on their third day in the election office. The officials called this an "error" and said the fact that it was quickly noticed and investigated proves that "the system of checks and balances set forth in Pennsylvania elections works."

People briefed on the matter told CNN that federal investigators are not treating the incident as intentional fraud but rather as something that occurred because of poorly designed procedures for handling mail-in ballots, and because newly hired election workers weren't properly trained.

You can read a full fact check here.

BALLOTS RECEIVED AFTER ELECTION DAY

Some states accept ballots that arrive after election day as long as they are postmarked on or before election day. But Trump suggested that these votes were illegitimate -- and that only Democratic states have such a policy.

"We have major states with that -- all run by Democrats. All run by Democrats," he said.

Facts First: Close to half of the states that accept late-arriving postmarked ballots are run by Republicans. There is nothing illegitimate about these votes.

According to CNN's latest tally, there are 25 states where it is legal for mail-in ballots that are postmarked on or before election day to be counted even if they are received after election day. Of those 25 states, 11 have Republican governors, including some ruby-red states like Mississippi, West Virginia and North Dakota.

Liberal groups have filed lawsuits across the country to allow more late-arriving ballots to be counted; the Trump campaign has been fighting such efforts. The liberals' efforts have prevailed in some key states, like Pennsylvania.

ELECTION RESULTS

Complaining of ballots being accepted after election day, Trump said a state that allowed ballots to come in until November 10 would mean ballots were arriving "seven days after the election in theory should have been announced."

Facts First: This is misleading. There is no requirement that the result of the election is announced on the night of election day. When we do know the winner that night, it is not because complete results have been tabulated by election authorities; it is because media outlets have used the available data to make a projection. Vote tallies always change after election day as absentee ballots and provisional ballots get counted; results that are publicly reported on election night are always "unofficial" and "preliminary." The official, final count is typically certified weeks later.