CALLS have been made for the main policing watchdog to be more open after it emerged key issues, such as security costings for the Commonwealth Games, are to be discussed behind closed doors this week.

The Scottish Police Authority (SPA)'s agenda for its latest monthly meeting of a key sub-committee tomorrow includes an update of the costings for the huge bill for policing Glasgow 2014.

The expected £90 million costs of 109,000 deployments of officers at the event are due to be met by the Scottish Government. However, Police Scotland's Deputy Chief Constable Steve Allen is to make a statement to the SPA's finance and investment committee which will be held in private tomorrow. A range of matters is to be heard in the closed session.

The SPA said the material contains confidential policing and commercially sensitive ­information, but would eventually be made public.

Labour MSP Graeme Pearson, a former deputy chief constable and Labour's Holyrood justice spokesman, has urged the authority scrutinise as much material as possible in public.

Mr Pearson said: "One of the rationales of the new national force was the absence of transparency and accountability under the old eight services. So the culture of the authority should be to discuss as much business as possible in public."

The SPA and its committees asserts a need to discuss in private disciplinary matters involving individual officers or commercially sensitive tenders.

The key finance committee, chaired by Glasgow Labour councillor Paul Rooney, has to deal with many such confidential issues. The committee, like the SPA, meets in public and discussions can be watched on a dedicated webcam. However, part of its meeting is closed to the public, with the webcam off. Minutes of these meetings are also closed.

However, Mr Pearson believes many off the questions on its agenda should be aired.

On the agenda of tomorrow's ­meeting, for example, is the final cost of policing the Commonwealth Games.

The massive security bill, met by the government and not the police, was one of the biggest ­operations in the history of the Scottish police.

The predicted costs tripled during preparations for the events. Tomorrow, Mr Allen will update the committee on how much was spent. But this will be heard in camera.

A separate report on how the force is handling its build-up of time off in lieu and postponed rest days that need to be re-rostered following the huge Commonwealth Games effort will also be heard privately.

Other items heard in camera will include the use of cash seized from criminals.

An SPA spokeswoman pointed out it has a statutory duty to conduct business in public, adding: "In 2013/14 we met in public twice as many times as previous scrutiny arrangements."

She added: "Police Scotland presents a number of papers on a variety of topics at the SPA board and SPA committees and we endeavour to ensure that as many papers are possible are presented and discussed in the public session of the SPA board and committees.

"Due to the nature of policing there is, at times, a requirement for some papers to be presented and discussed in the private sessions for a variety of confidentiality issues."

She said the 2014 Commonwealth Games updates were to be given in private because they contain confidential policing and commercial information. She stressed that they would be made public "at an appropriate time".