David Miranda: Goliath Strikes Back

The detention of the partner of a former Guardian journalist has triggered fresh concerns after it emerged that a key reason cited by police for holding him under terrorism powers was the belief that he was promoting a "political or ideological cause".

The revelation has alarmed leading human rights groups and a Tory MP, who said the justification appeared to be without foundation and threatened to have damaging consequences for investigative journalism.

David Miranda is the partner of Glenn Greenwald, the journalist who – often in collaboration with the Guardian – has broken many stories about the extent and scope of spying by the US National Security Agency. Miranda was stopped at Heathrow airport in August and held by the Metropolitan police for nine hours while on his way home to Brazil.

Miranda, it has been claimed, was carrying some 58,000 encrypted UK intelligence documents. He had spent a week in Berlin visiting a journalist, Laura Poitras, who has worked with Greenwald on many of his stories, which have been based on information leaked by the former NSA contractor Edward Snowden.

Now documents referred to in court last week before a judicial review of Miranda's detention shine new light on the Metropolitan police's explanation for invoking terrorism powers – a decision critics have called draconian...

The draft that was finally used states: "Intelligence indicates that Miranda is likely to be involved in espionage activity which has the potential to act against the interests of UK national security. We therefore wish to establish the nature of Miranda's activity, assess the risk that Miranda poses to national security and mitigate as appropriate."

The Observer.

And finally... Glenn Greenwald signs off from the Guardian.