He runs through a few possibilities posed by Iain Dale as to who authorised what in terms of surveillance, but Iain (and others) have missed the point that it seems that Khan was merely unintentionally caught up in a surveillance operation (allegedly carried out by the Anti-Terrorist Squad) where the prisoner was the target.
Iain rambles on trying to smear the government
The idea that a Labour Member of Parliament was being bugged and neither the Prime Minister or the Justice Secretary knew about it simply beggars beliefWell, actually it doesn't. The Justice Secretary is not involved in decisions about surveillance - they are a matter for the relevant authority - in this case, a senior police/intelligence officer or possibly the Home Secretary if telephone monitoring was required. If Khan was himself the target of the operation - as we can assume Gerry Adams, Sinn Fein MP for West Belfast was - then that would have required approval from the PM, in line with the Wilson agreement. In any case, the agreement isn't backed by law, so providing the law has been followed, there isn't actually a real legal problem here at all. As far as we know, however, Khan wasn't the subject, so the PM would not need to have been involved.
It isn't clear whether the Home Secretary would need to have been involved in authorising the operation, as there are powers for senior police and intelligence officers to approve such activities, but even so, the authorisation would have been for an operation against the named prisoner, not against Sadiq Khan, who was merely a collateral issue.
It isn't a scandal for the government, although I would be concerned as to how this information came to light, as it seems to have been leaked with the intention of causing political embarrassment.
This story has been in the possession of David Davis since December, yet only now does it hit the media - ideally placed to create enough noise to drown out the problems with Tory sleaze. Most expedient.