The UK gov's own website is a good source ;-) https://www.gov.uk/guidance/extradition-processes-and-review https://www.gov.uk/guidance/extradition-processes-an

The UK gov's own website is a good source ;-) https://www.gov.uk/guidance/extradition-processes-and-review https://www.gov.uk/guidance/extradition-processes-and-review > Extradition is prohibited by statute if: > the person could face the death penalty (unless the Secretary of State gets adequate written assurance that the death penalty will not be imposed or, if imposed, will not be carried out) EDIT: The UK has also denied extraction even though the death penalty is off the table. Example being Gary McKinnon. C+P from Wiki > On 16 October 2012, then-Home Secretary Theresa May announced to the House of Commons that the extradition had been blocked, saying that: > Mr McKinnon is accused of serious crimes. But there is also no doubt that he is seriously ill [...] He has Asperger's syndrome, and suffers from depressive illness. Mr McKinnon's extradition would give rise to such a high risk of him ending his life that a decision to extradite would be incompatible with Mr McKinnon's human rights.