UK gives full life tariff sentences in some scenarios. And even when full life tariffs aren’t handed down a life sentence does effectively last the rest of your life even if you are paroled, as you can be recalled to prison on the basis of your life sentence if further crimes are committed following parole. Also, the UK is considering leaving the ECHR which would allow them to reintroduce the death sentence if they so desired. Considering the way they stitched up innocent Irish for PR purposes over the years I’m not sure the UK having a death sentence would be a good idea though.