The top 10 most viewed fact-checks of 2015

From the presidential election to gun violence to federal spending, our top 10 most popular fact-checks for 2015 reflect some of the biggest issues of the past 12 months. Here, we count down those reports to the most popular fact-check of the year.

10. Ben Carson's Pants-on-Fire claim that no signer of the Declaration of Independence previously held office

Republican presidential candidate Ben Carson posted a note on Facebook to rebut critics who discounted him for his lack of experience in elected office. To bolster his point, the retired neurosurgeon wrote, "Every signer of the Declaration of Independence had no elected office experience." Carson soon changed the post to read, "Every signer of the Declaration of Independence had no federal elected office experience" (emphasis added).

About half or more of the declaration's signers had held elective office previously, including well-known figures such as Thomas Jefferson and Benjamin Franklin. Adding the word "federal" makes the claim nonsensical, as there was no federal government prior to the signing of the declaration.

Both the initial and the revised versions of Carson's claim are far off base. We rated Carson's claim Pants on Fire.

9. An Internet graphic said Hillary Clinton’s top 10 donors were mainly "banks, corporations and media," while Bernie Sanders’ top 10 donors were labor unions

A graphic going around social media painted Hillary Clinton’s list of donors as dominated by corporate interests, whereas Sen. Bernie Sanders’ top 10 donors came largely from labor unions -- a dichotomy that, to Democratic primary voters, put Sanders in a more favorable light. This contention fit quite closely with campaign data from the Center for Responsive Politics. However, it’s worth noting that this data refers to cumulative donations as far back as the 1980s, rather than just donations for their current presidential bids. We rated this claim Mostly True.

8. Viral post compares Honduras, Switzerland on gun laws and homicide rates

An image going around Facebook compared Honduras and Switzerland -- saying Honduras has extreme gun control and a high homicide rate, while Switzerland requires gun ownership but has a low homicide rate. The viral post aims to jolt readers with a counterintuitive implication: Gun laws can lead to deadly unintended consequences. But the post is flawed on many levels. Switzerland does not have the world’s lowest homicide level, and the post is flatly wrong about the laws in each country. Honduras doesn’t ban guns, while Switzerland doesn’t require ownership. This claim rates Pants on Fire.

7. Columnist Nicholas Kristof: More Americans killed by guns since 1968 than in all U.S. wars combined

In a column published shortly after the on-air slayings of two TV journalists in southwestern Virginia, the New York Times’ Nicholas Kristof offered some "data points" about the pervasiveness of gun violence in the United States, including: "More Americans have died from guns in the United States since 1968 than on battlefields of all the wars in American history."

The statistic holds up: There have been 1,516,863 gun-related deaths (homicides and suicides) since 1968, compared with 1,396,733 cumulative war deaths since the American Revolution. That’s 120,130 more gun deaths than war deaths. We rated Kristof’s claim True.

6. No, Internet, CNN did not delete its poll showing Bernie Sanders won the Democratic debate

A conspiracy theory rattled the Bernie-verse soon after many media outlets, including CNN, pronounced Hillary Clinton the winner of the first Democratic presidential debate. Some of Sanders’ supporters said no, Sanders was the clear winner as evidenced by a CNN poll, but CNN deleted the poll so as not to counter its narrative that Clinton won. However, CNN never actually deleted the poll. We rated this theory Pants on Fire.

5. A misleading pie chart of 'federal spending'

A pie chart circulating around social media purported to show federal spending, comparing military spending versus other programs. It claimed that 57 percent of federal spending goes to the military and just 1 percent goes to food and agriculture, including food stamps. But the pie chart cherry-picked just discretionary spending, which represents only about one-third of federal spending. Once you include mandatory spending, the military share plunges from 57 percent to 16 percent, and the categories that include Social Security, Medicare and Medicaid collectively account for a majority of federal spending. Spending on food and agriculture is still small, but it does quadruple from 1 percent to 4 percent.

The pie chart offered a deeply distorted picture of federal spending, so we rated it False.

4. Pants on Fire: "Denali" is the Kenyan word for "black power"

President Barack Obama decided to drop President William McKinley as the namesake of America’s tallest mountain, a move that some saw as an insult to the former president from Ohio. Anonymous social media critics pointed to a hidden motive in the mountain’s new name, Denali. An image circulating on Facebook accused the president of reaching back to his Kenyan roots for inspiration, claiming that " ‘Denali’ is the Kenyan word for ‘black power.’ "

The meme’s claim was ridiculous, though: "Denali" has roots in the word "Deenaalee" in Koyukon, a native language of Alaska. It approximately translates to "the High One" and has been used for countless generations by Alaska natives to describe the mountain. We rated the claim that it means "black power" as  Pants on Fire.

3. Obama's claim that we've seen "our deficits cut by two-thirds"

At his annual State of the Union address, Obama said that since he took office, the country’s deficits have gone down by two-thirds. The claim is accurate but ignores a stark reality about future deficits. The country’s spending is not expected to continue its downward route, according to federal forecasters, for reasons such as increased interest payments on the debt and the lack of substantial policy changes for the biggest programs, like Social Security and Medicare.

Further, the deficits have largely come down as a result of the improved economy for which Obama cannot assume full credit. We rated his claim Mostly True.

2. Obama: "This type of mass violence does not happen in other advanced countries. It doesn’t happen in other places with this kind of frequency"

After a gunman shot and killed nine worshippers at a historic African-American church in Charleston, S.C., in June, Obama pushed for more gun control. He said, "This type of mass violence does not happen in other advanced countries. It doesn’t happen in other places with this kind of frequency."

The data show that it clearly happens in other advanced countries, and in at least three of them -- Norway, Finland and Switzerland -- there’s evidence that the rate of killings in mass-shooting events occurred at a higher per-capita rate than in the United States between 2000 and 2014. The partial support for Obama’s claim is that the per-capita gun-incident fatality rate in the United States does rank in the top one-third of the list of 11 countries studied. On balance, we rated the claim Mostly False.

1. Trump wrongly said "thousands and thousands of people" in New Jersey cheered as the World Trade Center collapsed

The top spot goes to none other than Republican presidential candidate Donald Trump, who said he saw "thousands and thousands of people" cheering in New Jersey on 9/11.

All we found were a few news articles that described rumors of celebrations that were either debunked or unproven. What’s more there is no video or visual evidence to support Trump’s point. We suspect Trump may be confusing footage of people who were overseas and cheered the attacks. There’s nothing to support the notion that "thousands" in the United States cheered. We rated Trump’s claim Pants on Fire.