The seizure of journalists' notebooks, photographs and digital files could be conducted in secret hearings, owing to a little-publicised clause in a government bill aimed at cutting red tape, media organisations have warned.
Requests for notebooks, computer disks, photographs or videos must currently be made in open court and representatives of news groups can be present.
But the clause – in the deregulation bill, which comes before the Commons on Monday – significantly alters the way courts consider so-called "production orders", stripping out current safeguards.
The underlying rules governing whether police can have access to material will remain the same but without media groups being present it is feared that judges will be more easily persuaded to authorise police seizures of journalistic material.
Anxiety about the removal of parliamentary-backed safeguards has been heightened by a controversial production order case which the Metropolitan police are pursuing against the broadcaster BSkyB over a story involving claims that an SAS officer leaked information to a journalist.
The police applied to the court but did not serve all their evidence on Sky News. The charges have since been dropped but the Met has said it would like to be able to obtain production orders for "highly sensitive material" without having to disclose all its interests.
The Newspaper Society, which represents regional media, has written to the Cabinet Office ministers responsible for the bill, Kenneth Clarke and Oliver Letwin, protesting about the changes.
"The deregulation bill's provisions could enable the current statutory safeguards to be removed completely, reduced, weakened or otherwise radically altered at any later time, without prior consultation of the media affected nor detailed parliamentary scrutiny of the effect," the society has warned.
"Reporters are put at risk, whether reporting riots or investigating wrongdoing, if perceived to be ready sources of information for the police."
Responsibility for drafting new regulations has been handed over to the criminal procedure rule committee, chaired by the lord chief justice, Lord Thomas.
Gavin Millar QC, who is representing BSkyB in the police application case, said of the changes combined with the court case: "[They could] allow the police to use closed material proceedings [presenting evidence in secret before a court] in lots of cases. It's very worrying. The media will not be there to argue their case. Greater awareness of the information available in the digital age will [increase the number of applications]. The police have realised that there are vast quantities of information that may be of use to investigations. It's lazy policing basically."
The underlying rules governing whether police can have access to material will remain the same but without media organisations being present it is feared that judges will be more easily persuaded to authorise police seizures of journalistic material. One of the less prominent recommendations of the Leveson inquiry into media standards was that the Home Office should consider whether it should be easier for police to obtain journalists' information. Media organisations already face being charged with contempt of court if they do not comply.
A Cabinet Office spokesman said: "Every measure in the deregulation bill is intended to remove unnecessary bureaucracy. Clause 47 would bring the Police and Criminal Evidence Act into line with other legislation in this area and would allow the criminal procedure rules committee to make procedure rules that are consistent and fair.
" However, the government has noted the concerns raised about this issue and Oliver Letwin is happy to meet with media organisations about this before the bill goes to committee."
• This article was amended on 4 February 2014. The original said that the Leveson inquiry had recommended "that it should be easier for police to obtain journalists' information". This has been corrected.
