The WikiLeaks founder should face justice in Sweden, but the home secretary must make a formal undertaking that his approval for a second, onward extradition to the US will not be forthcoming, argues Naomi Colvin

Speaking as someone who knows and has quarrelled with Julian Assange, I feel that your description of him as an “unattractive character” (Editorial, 25 May) is a little ungenerous, but you are right to note the dire consequences of his being charged under the US Espionage Act of 1917.

The allegations against him in Sweden are an entirely separate matter. They have been left outstanding for far too long, in a way that is profoundly unsatisfactory to all sides. The Swedish allegations deserve to be heard on their own merits, without the threat of a second extradition from Sweden to the United States. Sajid Javid must make a formal undertaking that his approval for a second, onward extradition will not be forthcoming. That your editorial did not call for this is a surprising omission.

Naomi Colvin

London

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