Let's have a look at Tommy Robinson's Wikipedia article*:
> Robinson has a history of criminal convictions,[5] including for crimes such as assault,[6] threats,[7] harassment,[8] and fraud,[5] as well as contempt of court rulings relating to his videos, and has served five prison terms between 2005 and 2025. In June 2022, Robinson said that he lost £100,000 in gambling before declaring bankruptcy in March 2021. He also said he owed an estimated £160,000 to HM Revenue and Customs (HMRC). In August 2024, The Times said that he owed in the region of £2 million to his creditors, and was the subject of a HMRC investigation over unpaid taxes.
The Metropolitan Police are (justifiably) expecting this protest to turn into a violent riot, and have planned accordingly. British police forces have a long-established procedure for collecting CCTV evidence during riots, and then using that to prosecute rioters afterwards.