The National Union of Journalists has warned Local World titles that they risk becoming a "mouthpiece for police" if an experiment into police self-publishing on a newspaper website is extended across the group.
Police in Torquay last week published their first story directly on to the Herald Express website after being granted publisher rights to the paper's editorial system.
The news comes after chief executive David Montgomery said he wanted journalists to become "harvesters of content" supplied by third parties.
The union said: "David Montgomery’s distorted vision is to allow police, and other public and private organisations, to post their stories directly on to local websites.
"This is not a brave new vision of journalism, but a means to devalue the profession and cut editorial to the bone."
The statement from the MUJ ethics council reads: "The NUJ is strongly opposed to the idea of the police, or any authority or commercial organisation being able to publish directly to the local newspaper.
"It is the job of journalism, through local media, to hold local authorities, including the police, to account to local people. It is not its role to act as a conduit for the views and opinions of those authorities.
"If local authorities or the police wish to communicate directly with local people they should set up their own channels of communication."
Laura Davison, NUJ national organiser, said: "We know David Montgomery thinks that local journalists do a 'medium-grade craft' which could be carried out by 12-year-olds.
"He has a complete disregard for the vital role journalists have in their local community – holding local politicians and organisations to account.
"His vision is one which devalues the profession, will undermine the trust people have in their local paper and opens the doors for organisations with an agenda to directly control our local media. Readers won't stand for this and they won't pay for it either."