Firearms policing is to be reviewed by two of Scotland's most powerful watchdogs.

HM Inspectorate of Constabulary in Scotland (HMICS) and the Scottish Police Authority (SPA) - the formal ruling board of the new national force - are to join forces to look into increased visibility of armed officers.

The two bodies said they would carry out a "complementary programme of review and inquiry into the decision of Police Scotland to give a small number of firearms officers a standing authority to carry firearms".

Standard operating procedures for Scotland's armed officers gradually changed between 2008 and 2013 with local councillors previously responsible for policing failing to notice. The new police scrutiny regime will now examine "public concerns".

As revealed in The Herald earlier this year, the issue was highlighted when independent MSP and former police officer John Finnie became aware that armed officers were now carrying weapons in side holsters rather than in locked boxes in their vans.

This policy - routine through England and Wales where there are more police with guns - was introduced in the Northern Constabulary area weeks before the national force came into being. Armed units, meanwhile, were also charged with dealing with non-armed response incidents, increasing their visibility.

HMICS had already said it would carry out a assurance review on the changes but this will now be broadened to look at use of armed police on regular patrols and whether communities had been properly consulted.

The SPA, in parallel, has set up a scrutiny inquiry to consider the public impact of Police Scotland's decision around firearms deployment.

Led by SPA member Iain Whyte, it will investigate:

- what the level and nature of public concerns are over the current Police Scotland policy in relation to the standing firearms authority;

- how effectively Police Scotland are engaging with the public and considering the impact on communities in implementing their approach;

- how Police Scotland can best address any public concerns and provide necessary reassurance to communities, and;

- what, if any, lessons might be learned around how operational decisions with wider strategic or community impact are communicated to national and local oversight bodies and other key interests.

SPA will hold public hearings to gauge opinion.

Mr Whyte said: "SPA has acknowledged that the issue of armed policing is a contentious one, and that we would keep this issue under review.

"One of the principles of good governance is that the public voice is appropriately heard within decision-making. Questions and views continue to be raised about the issue and we have concluded

that an inquiry provides an opportunity for us to assess the level and nature of those concerns. That is an area where our initial phase of inquiry will focus.

"We also acknowledge that this is a specialist and technical area of policing. Our discussions with HMICS have identified a common set of operational issues that are worthy of review, and we feel they are ideally placed to provide us with the technical assessment of current policy and practice. Bringing together that public and professional evidence, and drawing findings and recommendations from them in a balanced and measured way, will be the ultimate objective of our inquiry."

Liberal Democrat Alison McInnes, a prominent critic of the new single force, said: "This is a victory for local communities.

"After months of pressure from Scottish Liberal Democrats up and down the country, the public and campaign groups, the SPA and HMICS have belatedly recognised that this fundamental change must be formally and thoroughly scrutinised. We need to know if the Scotland-wide policy on armed policing is proportionate to the risks in  individual communities in Scotland.

"After months of dismissing our concerns, Justice Secretary Kenny MacAskill must now change his tune and publicly back this review."

Derek Penman, HM Inspector of Constabulary in Scotland, said: "This review provides an opportunity for HMICS to make an objective professional assessment on whether the operational decision-making by Police Scotland on the standing authority for firearms has followed the relevant guidance, and that any conclusion is supported by the prevailing threat, risk, and available intelligence. This assurance role was requested by Police Scotland, but this will be an independent review with the remit and scope that we have assessed is necessary to fulfil our objective to add value and strengthen public confidence in policing.

"Engagement with the SPA has informed the scope of our work, and I am confident that our review will support the SPA in its wider scrutiny of armed policing. I believe this is a positive example of how different parts of the governance and scrutiny landscape in Scottish policing can work together in a complementary way with Police Scotland to improve outcomes for the public."

The HMICS review will be independent of the SPA inquiry but its report will the given to the SPA and discussed at a public meeting in October.

The SPA inquiry will then draw together both its own evidence and that of the HMICS assurance review, and report with overall findings and recommendations to the full authority at its public meeting in December.

Police Scotland welcomed the scrutiny. Deputy Chief Constable Iain Livingstone said: "Following this review and if a decision is made that the standing authority should remain in place, we will commission further work to consider alternative options for the carrying of weapons by armed officers.

"Police Scotland will also review the operational guidance provided to officers regarding the functions they perform when not engaged in firearms duties and consider how we may improve our engagement with communities.

"Our policing purpose is to keep people safe against all potential threats. The differences in specialist firearms protection to communities and unarmed officers prior to Police Scotland was unacceptable and inequitable.

"By having a small number of specially trained firearms officers available 24/7, we can ensure that all communities have equal access to this specialist police capability. We look forward to considering any recommendations that come from the reviews announced today."