The UK’s anti-terror law watchdog has said that the police should not be able to detain people at the UK’s borders without any suspicion of wrongdoing, following the detention of Glenn Greenwald’s partner who was carrying documents leaked by Snowden.

David Anderson QC, the UK’s independent reviewer of terrorism legislation, has advised the House of Commons home affairs committee that schedule 7 of the Terrorism Act should be changed, it was reported in the Guardian Monday.

Schedule or section 7 allows police officers to stop, search, question and detain individuals for up to nine hours at airports, ports and border areas without any previous suspicion to determine if they are “concerned in the commission, preparation or instigation of acts of terrorism”.

"My recommendations for further reform include the introduction of a suspicion threshold for the exercise of some schedule 7 powers, and the improvement of safeguards in relation to private electronic data and other sensitive material of various kinds, I do not believe that anything in my recommendations should reduce the efficacy of what is a very useful set of powers, or expose the public to additional risk from terrorism," Anderson said.

However, the QC stopped short of advising “reasonable grounds for suspicion” before detention, as some campaigners had hoped for.

Under Anderson’s new proposals the police would still be able to search and question passengers without any previous grounds for suspicion but only for up to an hour, after which there would need to be an extra threshold test of genuine suspicion.

He also said that the same criteria should apply to any data, which is obtained from the individual being detained.

Anderson also said that any admissions by someone being questioned during a schedule 7 interview should not be used in a subsequent criminal trial.

The controversial law was put under the spotlight after a number of incidents this summer, the most high profile of which was the nine hour detention of David Miranda, the partner of Glenn Greenwald, who was involved in exposing US and UK spying leaked by whistleblower Edward Snowden to the Guardian. At the time of Miranda’s detention Greenwald worked for the Guardian.

Miranda was detained at London’s Heathrow airport while returning to Rio de Janeiro from Berlin where he had been visiting US film maker Laura Poitras who had also been working with Greenwald and the Guardian on Edward Snowden’s revelations about US and UK mass surveillance. Miranda says that electronic equipment including his laptop, mobile phone, camera and memory sticks as well as game consoles were all confiscated from him. He had been transporting documents leaked by Snowden to Greenwald and his flight was paid for by the Guardian.

Miranda has sought a judicial review of his detention; and says that it breached his human rights and demanded that materials seized from him be returned. His case was heard on the 6 and 7 November, although the judgment has not yet been handed down.

The legislation has also been challenged under the European convention on human rights in May and by the supreme court and parliament’s joint committee on human rights in October. Judges in the UK’s supreme court voiced their concern that the power to stop, question and detain at ports was not subject to any controls and was left solely to the policeman or intelligence officer on the scene.

Last year alone about 60,000 people were questioned under schedule 7 and only 670 of those were formally detained.

The Home Secretary, who is already under fire for her handing of a number of sensitive asylum cases, will now be under further pressure to change the antisocial behavior, crime and policy bill to include Anderson’s recommendations. The bill has already contains a clause currently going through parliament to reduce the maximum amount of time the police can detain an individual from nine to six hours.

“I’m very pleased to see David Anderson’s recommendations for further constraints on schedule 7. His suggestion to require grounds for suspicion for detention and constraints for the use of private electronic data are very welcome,” Julian Huppert, a member of the home affairs committee, told the Guardian.

Following Miranda’s detention in August the shadow home secretary Yvette Cooper, called for an urgent investigation into the use of schedule 7 by the authorities.

“Any suggestion that terror powers are being misused must be investigated and clarified urgently. The public support for these powers must not be endangered by a perception of misuse,” she said.

A Home Office spokesman could not confirm if Anderson’s recommendations would be accepted and said “Schedule 7 forms an essential part of the UK’s security arrangements at the border”.