A man who says he suffered a depressive illness as a result of discovering his father was an undercover police officer rather than a political activist has won the latest round of a High Court compensation battle with the Metropolitan Police.

The 32-year-old sued Metropolitan Police Commissioner Cressida Dick, arguing that the force head was responsible for his father and the officers supervising him.

But lawyers representing the force asked a judge to dismiss the man's claim entirely - arguing that there were "no reasonable grounds". Mr Justice Nicol on Monday refused to take such a step.

The judge said the man might win compensation if he demonstrated that supervising officers had failed to provide a "duty of care" they owed him.

Mr Justice Nicol, who analysed the issue at a High Court hearing in London in October, has not named the man in a written ruling.