Earlier quoted context omitted.
That's one way of looking at it. Another: a warrant was issued for his arrest in relation to a crime that was accused. He used a foreign embassy to avoid that arrest. Giving up would not be setting a fantastic precedent for future alleged criminals who do not wish to answer questions. (EDIT: changed "committed" to "accused" as per discussion below)
Isn't it right of any government to grant sanctuary, though?
Not setting that precedent is likely one of the main reasons the UK wasted so much money on policing.