Assaults spiked on Trump rally days during 2016 election

Cities experienced 2.3 more assaults than average on days when hosting presidential campaign rallies for Donald Trump during the lead-up to the 2016 United States Presidential Election, according to a first of its kind study published online today in Epidemiology by researchers in the Perelman School of Medicine at the University of Pennsylvania. Hillary Clinton rallies were not linked to any increase in assaults, they found.

"News media sources reported there were violent incidents at some campaign rallies, but it was difficult to gauge whether there really was a systematic problem, and if so, how many additional assaults were associated with each rally," said the study's lead author, Christopher Morrison, PhD, MPH, a fellow in Penn's Center for Clinical Epidemiology and Biostatistics and an epidemiologist in the Penn Injury Science Center. "To prevent similar violence in the future, it is important to understand the underlying causes of this behavior, perhaps including the role that political rhetoric might play in normalizing or promoting violence."

Focusing on cities of greater than 200,000 people, the team performed a systematic Google search and found publicly available data for 31 rallies in 22 cities for Trump and 38 rallies in 21 cities for Clinton. Using assault data from police departments in those cities, including aggravated assaults, simple assaults, and/or battery, the team counted assaults on the day of each rally. For comparison, they also counted assaults on corresponding days of the week for four weeks before and four weeks after each rally.

Rallies in the study were defined as open invitation events that occurred after Donald Trump and Hillary Clinton declared their candidacies in spring 2015 and before the U.S. Presidential Election on November 8, 2016, featured a speech by Trump or Clinton, and were not on the same day as a party primary election in the same state as the rally.

The researchers suggest two possible explanations for their findings. First, all additional assaults could have occurred in and around the venues of candidate Trump's rallies where people invested in the process gathered. This explanation is consistent with news media reports that violence occurred at these specific locations. Second, additional assaults that took place might have occurred elsewhere in the rally cities. Studies informed by theories of social contagion find evidence that emotional states can be transmitted through and digital social media, which could have led to more assaults occurring away from the rally sites.

The researchers note that Trump rallies were widely broadcast and discussed through news reports and digital social media, such as a rally in Cedar Rapids, Iowa during which candidate Trump remarked that he would "knock the crap out of" would-be hecklers at the event, and other examples from the non-partisan POLITIFACT.

"This research provides evidence that this increase in assaults is associated with candidate Trump's rallies leading up to the election," said senior author Douglas Wiebe, PhD, an associate professor in Epidemiology. "Violent language may have affected the mood and behavior of rally attendees, as well as those exposed to the rally through news reports and social media."

The researchers added that weather can also influence crime rates, so the team consulted National Oceanic and Atmospheric Administration data for the weather station nearest to each study to control for temperature and precipitation.

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Journal information: Epidemiology

Citation: Assaults spiked on Trump rally days during 2016 election (2018, March 16) retrieved 17 October 2019 from
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User comments

Mar 16, 2018
Yes, the attacks were indeed systematic...against Trump supporters. The thugs were paid and delivered to the scene. The fake media ignored them, by in large.

Mar 16, 2018
The intolerance of liberal thugs, proudly announcing their hatred of conservatives while displaying their "Coexist" stickers on their Prius'.

Mar 16, 2018
Individuals associated with the alt-right movement, championed by Bannon and Trump have killed more than 48 people in the last 15 years.
'Homegrown Extremists Tied to Deadlier ... 48 people in the United States have been killed by ... "And there's a belief that the threat of right ...'

Mar 17, 2018
A very vague picture at best.
Among other things, who attacked who first? Were the attacks simple assault, not battery? Were they battery? Did one group commit more battery cases than the other?
Importantly, just as with guns, it is unreasonable, under conventional thinking, to say the presence of a rally actually made people who would be doing something else otherwise to engage in violence or was it the people themselves who decided to engage in violence?
And which group engaged in causing more violence, Democrats or Republicans?
And how do numbers from past elections, with other candidates, compare?

Mar 18, 2018
Right wing trolls on a science site? Ones that I don't recognize from climate articles?

Internet Research Agency is really reaching here, methinks.

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