Surprise: White Power violence is connected to Trump rhetoric

Using the Anti-Defamation League’s Hate, Extremism, Anti-Semitism, Terrorism map data (HEAT map), we examined whether there was a correlation between the counties that hosted one of Trump’s 275 presidential campaign rallies in 2016 and increased incidents of hate crimes in subsequent months.

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We included controls for factors such as the county’s crime rates, its number of active hate groups, its minority populations, its percentage with college educations, its location in the country and the month when the rallies occurred.

We found that counties that had hosted a 2016 Trump campaign rally saw a 226 percent increase in reported hate crimes over comparable counties that did not host such a rally.

Of course, our analysis cannot be certain it was Trump’s campaign rally rhetoric that caused people to commit more hate crimes in the host county.

  WaPo

I don't think we need "certainty" to make the call on this.

Research shows it is far more likely that hate crime statistics are considerably lower because of underreporting.

Additionally, it is hard to discount a “Trump effect” when a considerable number of these reported hate crimes reference Trump. According to the ADL’s 2016 data, these incidents included vandalism, intimidation and assault.

What’s more, according to the FBI’s Universal Crime report in 2017, reported hate crimes increased 17 percent over 2016. Recent research also shows that reading or hearing Trump’s statements of bias against particular groups makes people more likely to write offensive things about the groups he targets.