>observers claimed he was delusional to think he would be charged with a capital crime (meaning he could be executed if convicted), because that would violate the terms of any extradition.
While the Foreign Office may insist that we will never extradite if there is a possibility of the death penalty, the Home Office on the other hand can take it upon themselves to waive that requirement and have apparently done so recently in another case, so it is possible and the UK is quite prepared to say that it isn't, while doing it - https://www.bbc.co.uk/news/uk-44929067
While the Foreign Office may insist that we will never extradite if there is a possibility of the death penalty, the Home Office on the other hand can take it upon themselves to waive that requirement and have apparently done so recently in another case, so it is possible and the UK is quite prepared to say that it isn't, while doing it - https://www.bbc.co.uk/news/uk-44929067