In evidence submitted to Holyrood’s Finance and Public Administration Committee, David Kennedy, the SPF’s general secretary, said the inquiries were exacting a “crippling” toll on a service already experiencing its lowest staffing levels since Police Scotland’s inception. The committee is reviewing the cost-effectiveness of public inquiries amid growing concern over their expense and impact.

Mr Kennedy highlighted that the inquiry into the death of Sheku Bayoh had already cost the force more than £20 million. Mr Bayoh died in 2015 after being restrained by officers in Kirkcaldy. Another inquiry, into the investigation of the murder of Emma Caldwell, is expected to run for several years and absorb millions in police resources.

Mr Kennedy said: “Each of these inquiries demands significant input from the police service in terms of legal support, evidential preparation, officer time, and administrative resources. Taken collectively, they represent a crippling financial and operational burden on a service already facing the most acute resourcing crisis in over a decade.

“Police Scotland operates with its lowest officer numbers since its creation, with frontline services under relentless pressure and no capacity to absorb additional workload. Yet, time and again, officers are abstracted from their core duties to meet the requirements of public inquiries often for months or years at a time with no dedicated budget, no additional staffing, and no structured engagement in the planning of those inquiries other [than] that in which the police have to do so. This is not sustainable. It is not fair on our members, and it is not in the public interest.”

He said the pressures were being absorbed by “reallocating staff, reducing local presence, delaying investigations, and increasing the burden on already overstretched colleagues”. He added: “To believe that public safety hasn’t been compromised would be foolhardy. Officer wellbeing is being totally neglected and we are seeing more and more officers wanting to leave the service.”

To address these concerns, Mr Kennedy made four recommendations to the committee. He called for legislation to ring-fence funding for police-related inquiry costs and for a statutory pre-inquiry assessment process. He also urged reforms to inquiry structure and governance, including enforceable controls over their scope, duration and financial oversight.