Scotland's chief police officers face "a near total wipe-out" over the next year as months of high-stress scrutiny take their toll.

Under constant political and media fire, fully two out of three deputy and assistant chief constables will quit or retire within the next 12 months, The Herald understands.

Senior insiders believe the national force is now heading for an unprecedented "change of the guard" with potentially dramatic cultural changes to follow as a result.

Chief Constable Sir Stephen House, pictured below, stands down early next month with two his four deputies - Iain Livingstone and Neil Richardson joining English officer Phil Gormley on a three-man shortlist to replace him.

But sources familiar with the highest ranks in the country stress change will not just effect the very top.

One said: "We are looking at a near total wipe-out in the chief officers' corridor. This will be an unprecedented change of shift.

"There are currently a dozen chief officers but there is unlikely to be more than four of five of them left by this time next year.

"Almost all of them have served 30 years and could retire if they choose to do so.

"Some have already said they are going. All the politics is taking a toll.

"There are officers who have worked hard and served the country well who are now being called 'fat cats' or 'incompetents' in the papers and some have just had enough."

All four deputy chief constable (DCC) posts are all likely to be up for grabs.

Mr Livingstone, pictured above, and Mr Richardson will either be promoted or leave, say insiders. Their two colleagues, Rose Fitzpatrick and Steve Allen are also set to go in the next 12 months.

Last week a tabloid claimed Mr Allen, earned more than £700,000 a year, more than any other officer in the UK, after conflating pension benefits, multiplied by 20 in police accounts for technical reasons, with his real earnings. The paper also printed inflated income figures for Mr Livingstone and Mr Richardson.

The actual DCC earnings of around £170,000 are not enough to keep Mr Allen in post. The veteran, pictured below, is retiring after exactly 30 years service.

Despite "fat cat" pension headlines ,sources stress that tax disadvantages with staying in the police pension scheme for more than 30 years is incentivising officers to leave.

Most of the current crop of chief officers joined in the 1980s.

Ms Fitzpatrick, who signed up in 1987, is understood to have signalled that she is unlikely to serve beyond her current contract, which ends next year.

Police Scotland also has seven assistant chief constables (ACCs), each earning around £110,000. Speculation is rife four or five of them may go, with all but one being 1980s recruits and hitting the 30-year pension wall.

One ACC, Wayne Mawson, is facing an investigation in to gross misconduct for alleging cheating in on a command course he had to pass to keep his job.

Pictured below, Mr Mawson has been removed from the operational frontline.

There is particular concern within the force that the number of women in the most senior positions may fall.

ACCs Val Thomson - whose current brief includes controversial call handling reforms - and Kate Thomson, who is in charge of uniformed policing in eastern Scotland, are seen as possible departures despite their relatively recent appointments. Along with the Ms Fitzpatrick, they make up the entire female contingent among chief officers.

A source said: "There are not many women coming through the ranks with the qualifications. Police Scotland may need to go to England for senior women."

Former Strathclyde officer Fiona Taylor, a deputy assistant commissioner in the Metropolitan Police, has been linked with a return to Scotland.

There are those in Police Scotland who see the generational change of the guards as a real chance for who-ever replaces Sir Stephen to stamp his (there are no potential female replacements) worldview on the organisation.

Another insider said: "Many will see this as a failure in planning. In truth, it is a tremendous opportunity to completely refresh the leadership of the service, which should be relished by the new chief constable."

The current top team and their future.

Chief Constable Sir Stephen House

Joined 1981

Background: Sussex, Staffordshire Police & Met

Status: Retiring early

Deputy Chief Constable and designated deputy for the chief constable Neil Richardson

 Joined 1985

Status: Applying for chief constable job

Background: Lothian and Borders and Strathclyde Police

Deputy Chief Constable for Crime and Operational Support Iain Livingstone

 Joined 1992

Status: Applying for chief constable job

Background: Lothian and Borders

Deputy Chief Constable for Major Events Steve Allen

Joined 1985

Status: Retiring

Background: Avon & Somerset, Metropolitan and Lothian and Borders

Deputy Chief Constable for Local Policing Rose Fitzpatrick

Joined 1987

Status: Active but expected to leave within a year

Background: Metropolitan

Police Assistant Chief Constable for Major Crime and Public Protection Malcolm Graham

Joined 1995

Status: Active, tipped for DCC role or continued work in Police Scotland

Background:

Lothian and Borders Police

Assistant Chief Constable - Operational Support Bernie Higgins

Service: Joined 1988 Status: Active, tipped for DCC role or continued work in Police Scotland Background: Strathclyde Police

Assistant Chief Constable for Organised Crime & Counter Terrorism Ruaraidh Nicolson

Joined 1983

Status: Active but has served his 30 years.

Background: Strathclyde Police

Assistant Chief Constable for Contact, Command and Control, Custody Val Thomson

Joined 1988

Status: Active but under pressure as officer in charge of implementing call handling reforms

Background: Strathclyde Police

Assistant Chief Constable for Local Policing North Derek Robertson

Joined 1986

Status: Active but approaching his 30 years next year

Background: Strathclyde

Police Assistant Chief Constable for Local Policing East Kate Thomson

Joined 1985

Status: Active but has served her 30 years

Background: Dumfries and Galloway Police

Assistant Chief Constable for Local Policing West Wayne Mawson

Joined 1988

Status: Moved to non-operational role pending investigation for gross misconduct

Background: Metropolitan and Strathclyde Police