Hello and welcome back to the bunker bringing you news and politics explainers every morning.

I'm Andrew Harrison.

Over the past week, England and Northern Ireland have been convulsed by the worst civil disturbances

we've seen since the riot of 2011 and the worst far right violence of the post-war era.

We've seen mosques besieged arson at a so-called migrant hotel and the library in Liverpool, assaults

of ethnic minorities on the street and some 400 arrests to date.

And as increasing numbers of the riders appear in court, there's often a pattern to what

they say.

They didn't understand what they were getting into.

They're deeply ashamed of their uncharacteristic

behavior. They'd been drinking. Once their old defendants even wept in the dock and

asked for his mom. These riots are unique in recent British history in that

they are explicitly triggered by far

I agitation. The former head of counterterrorism policing, Neil Bassu, described it as terrorism.

But they do raise a question, why do people riot?

What draws people into civil disturbance and then leads them to pick up a brick?

Is it really mindless violence or something more complex?

Professor Clifford Stott is visiting professor at Ohio State University

with a specialism in the psychology and dynamics of crowd behavior,

including riots, hooliganism, and public order policing. He's also the director of Enable, which looks at the policing of football crowds and is funded by the Football League.

He's been involved in planning the policing of major football tournaments and he's a Liverpool fan, so that's a good thing.

Professor Stough, thank you for joining us.

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