Scotland's justice secretary has been urged to ensure new Police Scotland guidelines do not have a "chilling effect" on internal critics within the force.

The new rules require officers to declare any associations they have with journalists and politicians, raising concerns they will be used to quash whistleblowing.

The guidance is compulsory for all police officers and special constables, with the prospect of misconduct proceedings for anyone who breaches it.

It is part of the force's latest anti-corruption strategy and aims to "protect the information, assets and reputation of Police Scotland".

Scottish Liberal Democrat leader Willie Rennie claimed a political and media register would have a "chilling effect".

He said "declaration of media and political contacts" by officers is "designed to snuff out such contacts rather than to aid transparency".

Rennie has called on justice secretary Michael Matheson and the Scottish Police Authority (SPA) to intervene to make sure "the police hierarchy are not free to silence internal critics".

The Scottish Government described the rules change as an "operational matter" for Police Scotland but said all public services should "recognise the importance of engaging with MSPs and journalists".

It added there should be "an open and transparent reporting culture across all levels of the service".

Police Scotland insists the guidance has been "misrepresented as an attack on police officers" and was widely consulted on, adding it provides separate guidance for staff in relation to whistleblowing.

The rules are contained in a 19-page document laying out the latest standard operating procedure (SOP) for "notifiable associations".

Associations officers must report include:

Officers need to declare any connections, friendships, "intimacy" or meetings with people they know in these categories, including people they know through groups and societies such as sports clubs or people they know through social media.

The rules are to designed to prevent officers from being personally "compromised", compromising Police Scotland's operations or reputation or compromising members of the public.

Rennie pointed to collaboration between "principled police officers and staff" and journalists or MSPs in the course of exposing "deep-rooted flaws in Scotland's police service".

He said: "These people should be hailed not silenced.

"The M9 crash, the chaos in the control rooms, the back filling of civilian roles by police officers, the near misses, armed police on routine duties.

"All of these issues were exposed in part through the assistance of police staff and officers who cared about the future of the police service."

Rennie added: "A declaration of media and political contacts is designed to snuff out such contacts rather than to aid transparency.

"The Leveson inquiry investigated these matters and we must be careful to learn the lessons but a political and media register would have chilling effect and would enable those in charge to escape the necessary scrutiny.

"The justice secretary and Scottish Police Authority should intervene to ensure that the police hierarchy are not free to silence internal critics."

A Scottish Government spokeswoman said: "The guidance is an operational matter for Police Scotland.

"It is right that all public services recognise the importance of engaging with MSPs, journalists as well as other key stakeholders.

"We also believe that it is important staff are provided with a safe space to discuss any concerns and promote an open and transparent reporting culture across all levels of the service."

A spokesperson for the SPA said: "The SPA approved the anti-corruption policy which aims to protect the integrity of policing in Scotland and prevent and detect corrupt behaviour.

"It is for the chief constable and Police Scotland to ensure that policy is adhered too, this could be through formal SOPs or guidance.

"The SPA recognises the importance of having an environment where individuals feel confident and have the opportunity to come forward and raise concerns.

"The board recently approved a formal whistleblowing policy which provides a range of opportunities to raise concerns directly with the organisation or through an online confidential reporting system."

Chief superintendent Alan Speirs, head of professional standards for Police Scotland, said the purpose of the SOP is "to protect the integrity of officers and staff from any threat posed by notifiable associations".

"Associations are clearly defined as instances which has the potential to compromise an individual, an operation, Police Scotland or members within our local communities," he continued.

"This SOP is line with all UK forces who receive appropriate guidance from the National Crime Agency.

"The SOP is not new and the changes reflect the current threats and risks posed by a number of notifiable association categories. It was widely consulted on, and includes all staff associations."

Mr Speirs added: "This should not be misrepresented as an attack on police officers or police staff or to stop them from raising legitimate concerns.

"This policy should not be confused with our guidance to officers on whistleblowing.

"The guidance on politics refers specifically to membership of political parties where that member plays an active part - this is far removed from reported 'MSP links or politician contacts', and this entirely misrepresents the policy.

"So too do references to journalists, media and press - this guidance refers to where there may be a potential conflict with Police Scotland operations/investigations."