SENIOR police officers should not have to justify the cost of major investigations such as murder and missing person inquiries, and should instead be allowed to get on with their job, according to a representative body.

The Association of Scottish Police Superintendents (ASPS) has raised concerns following suggestions senior officers may be questioned by the Scottish Police Authority (SPA) – the body which will oversee the new single police force – on operational decisions.

ASPS president David O'Connor said he will raise the issue with the SPA board. The concerns follow comments by SPA member Iain Whyte at the weekend in which he stated there are no "no-go areas when assessing best value". He said such scrutiny was not about second-guessing officers but about "making sure they are making the right decisions".

However, the ASPS said it was the job of the chief constable to appear before the SPA to account for spending decisions.

Mr O'Connor said: "I welcome firm and robust scrutiny of the chief constable by the SPA but I would be concerned if they wanted to scrutinise individual senior investigating officers – this is firmly in the operational sphere and these officers should only be accountable to the chief constable."

The concerns follow a power struggle between the new single force's Chief Constable Stephen House and SPA chairman Vic Emery over control of police support staff.