Not simpler to extradite him then and there, but simpler to extradite him at some point in the future, assuming the investigation would've been successful
Edit: HN doesn't let me reply so deep in a thread unless I wait like 20 minutes. It'd have been simpler if he were detained as they'd have had a guarantee of his jurisdiction and plan accordingly. I imagine having him arrested in a country that had allowed CIA extraordinary rendition would've been better for them than having him protected in Ecuadorian embassy.
He was in Britain for over a year before he entered the embassy. As you can see now, the UK authorities would have arrested him in response to an extradition request.
Edit: HN doesn't let me reply so deep in a thread unless I wait like 20 minutes. It'd have been simpler if he were detained as they'd have had a guarantee of his jurisdiction and plan accordingly. I imagine having him arrested in a country that had allowed CIA extraordinary rendition would've been better for them than having him protected in Ecuadorian embassy.