Those close to Mr. Starmer say he is getting a grip on the disorder, drawing on his experience as a chief prosecutor in 2011, when riots took place in London and he pushed to get those responsible tried, sentenced and jailed swiftly to deter others.
“He has a detailed knowledge of how to do this, and he understands how you prosecute and convict quickly, and you do so visibly in a way that sends a message to anybody who is thinking about participating in one of these riots,” said Claire Ainsley, a former policy director for Mr. Starmer.
But ensuring that such violence does not recur is harder, she said.
“We have had the far right with us in good economic times and in bad economic times,” said Ms. Ainsley, who now works in Britain for the Progressive Policy Institute, a Washington-based research institute.
“But it is much harder for them to have any kind of influence when you are in better economic times,” she added. “That means people’s living standards rising and people starting to feel they are better off and that they are part of a system that is working — and that isn’t a description of Britain today.”
Ms. Ainsley pointed to the role of social media in spreading misinformation and stoking tensions, and cautioned against making a direct link between the riots and immigration. She noted that, alongside extremists, some of the rioters may be looters and other opportunists.
It is, she added, “wrong to assume that all of the people participating in these riots are politically motivated by immigration.”
