"U.S. police killed more people in just one month than the U.K.’s did in over a century."

Addicting Information on Saturday, April 4th, 2015 in an infographic on the Addicting Info website

Liberal blog: U.S. cops killed more people in one month than U.K. cops killed last century

Pallbearers walk Walter Scott's casket to the gravesite for his burial service in Charleston, S.C. on Saturday, April 11, 2015. Scott's death at the hands of a North Charleston, S.C., police officer reignited calls for more police accountability. (AP)

As the country learned about the shooting death of Walter Scott in North Charleston, S.C., a comparison between police in the United States and the United Kingdom began to spread across the Internet. The liberal website Addicting Info put up a graphic under the headline "U.S. Police killed more people in just one month than the U.K.’s did in over a century."

Other groups made similar claims -- including RT, the English language cable channel financed by the Russian government.

According to Addicting Info:

U.S. police killed 111 people in March 2015

U.K. police killed 69 people from 1900-present.

A reader asked us to check it out.

Tracing the source of the data

Addicting Information used this eye-catching graphic to tell its story. 2015-04-14 12_15_46-Greenshot.png

You won’t find this image on the Addicting Information website any longer.

Elisabeth Parker, the author of the piece, explained to us where she got her information. She started with a post that made a similar but not identical claim on Daily Kos, a liberal website. The post’s count of American deaths in March tracked back to a website called Killed by Police.

Killed by Police has a singular task. Each time a television station or newspaper reports that a person has died at the hands of the police, the people behind Killed by Police (we don’t know who they are) add a link to the news story in a spreadsheet. When we saw the list for deaths in March, it had 115 entries.

We read each news report and found that just about every death, 98 of them, involved a police shooting. There were 16 cases when a person died from other causes, most frequently when police used a taser. One time an officer accidentally hit and killed a person with his car. In a category by itself, an officer in Hawaii got into an argument with a neighbor and killed him, thus becoming a common murderer completely apart from his role in law enforcement.

The warning here is the warning with all fact-checks and analysis of police-related deaths. There is no singular, verified U.S. database of police shootings. So all we have are estimates.

In this case, University of Missouri-St.Louis criminologist David Klinger said the Killed by Police numbers -- whether you settle on 98, 111 or some other figure -- "wouldn’t be unexpected."

Deaths in the United Kingdom

So, yes, the U.S. figure for March is plausible.

But this claim really hinges on the stat encompassing more than 100 years in the United Kingdom.

The fact is, that relies on a Wikipedia list of killings by law enforcement officers in the United Kingdom.

"I pored over the Wikipedia entry and realized that some incidents included multiple shootings and adjusted (the) figure to 69 police shootings," Parker said.

The problem with that is that Parker had to make two big assumptions: That the list was accurate, and more critically, that it was complete.

With Wikipedia, those are assumptions people should not make. In fact, the Wikipedia entry warns at the top that "This list is incomplete."

So what’s the real number? Over such a long time horizon -- and in a country whose borders changed (Ireland was part of the United Kingdom until the 1920s) -- it’s really impossible to say.

The British advocacy group Inquest has looked at police incidents in England and Wales going back to 1990. By its count, there were 55 police shooting deaths between 1990 and the present. The group reports another 1,453 deaths that had some connection to contact with police. However, the causes range from someone dying of a drug overdose while at a police station, to car thieves killing themselves in a wreck, to suicide while in custody, to excessive use of force by officers.

There simply is no way to tease out the details. Comparing police shootings to the American data is the only reliable approach.

The only other country in the United Kingdom for which we found hard numbers was Northern Ireland. Between April 2008 and September 2014, roughly a six-year period, members of the Police Force of Northern Ireland discharged their weapons nine times. However, there is no data on whether any deaths resulted.

During the times of "The Troubles" from 1968 to about 2000 when separatists, generally Catholics, and unionists, generally Protestants, battled over whether Northern Ireland should break away or remain part of the United Kingdom, there were over 3,000 deaths. Some of those were at the hands of the police.

Aogan Mulcahy, a researcher in the School of Sociology at the University College Dublin, walked us through the numbers. The Royal Ulster Constabulary was the police force in Northern Ireland until 2001. Based on an online database, Mulcahy told us that the RUC "was responsible for 55 deaths over the period 1969-2001."

We found no information for Scotland. We should note that only the Northern Ireland police regularly carry firearms. In Scotland, Wales and England, the typical officer relies on less lethal equipment such as nightsticks, pepper spray and tasers.

In sum, we know Wikipedia’s count is far low, but we don’t know how low.

When we alerted Parker to the information we were finding, she retracted her original article and wrote another. Parker wrote that "U.S. police killed more people in one month than the U.K.’s did in an entire year." While the underlying numbers this time are still incomplete, that’s more accurate.

Our ruling

Addicting Information said that "U.S. police killed more people in just one month than the U.K.’s did in over a century."

This comparison was based on an incomplete Wikipedia list. While hard figures for the number of police-related deaths in the United Kingdom over more than a century are impossible to come by, our research shows the comparison is inaccurate.

It’s certainly unproven.

That makes it deeply flawed, which means it’s False.