The length of time roads have to be closed to allow police to investigate serious accidents is to be cut significantly thanks to the latest technology.

Police Scotland has confirmed new 3D laser scanners will be deployed on Scotland's roads by the spring in a move that could revolutionise the way officers investigate crashes.

The move comes amid concern in Scotland over how long it takes to re-open major roads after accidents. Two weeks ago there was a five-hour closure of the M8 eastbound carriageway after two people were injured in a four- vehicle accident near Glasgow.

It can be more serious in rural areas. Motorists faced a 150-mile detour via the A9 in July when Fort William was effectively cut off from the south for hours following a fatal accident on the A82 near the villages of Onich and North Ballachulish.

Last week one MSP called for a study into the impact on the tourist industry and local businesses of the frequent closures of the main road arteries to the West Highlands.

Superintendent Iain Murray, head of road policing, said buying the new collision investigation equipment had been agreed and it was hoped it would be deployed before the end of the financial year. "It will further reduce the time spent gathering data at collision scenes," he said.

Forces began using the equipment south of the border last year.

The scanner, which costs about £50,000, slowly rotates 360 degrees, recording up to 120,000 different details of a crash scene every second. It allows police to cordon off the crash scene and recreate a virtual copy of it from outside, rather than investigators entering the site and painstakingly surveying every aspect of the scene.

The digital image can then be viewed on a computer screen remotely, allowing police to measure where vehicles are in relation to each other and other physical features of the scene.

It can also be developed for use in court to support or contest statements from drivers and witnesses.

Early trials in England in 2009 showed the laser scanners could reduce incident clear-up times by an average of 39 minutes. But the time saving can be a lot more.

Jamie McGrigor, Tory MSP for the Highlands and Islands, is concerned about the time police take to reopen the roads after accidents, particularly when fatalities are involved.

Neil Greig, director of policy and research at the Institute Of Advanced Motorists, said road crash investigations had become more thorough since a change to human rights legislation.

He said: "What has happened in recent years is that police investigating death and injury have to treat the scene as a crime scene and that adds a lot of extra time. It is a difficult balance.

"The family of anyone killed or seriously injured in Scotland's roads has the right to know the death of their loved one has been fully investigated, whilst others just want to go about their business. "

Mr McGrigor said he looked forward to the laser technology being introduced as soon as possible, particularly on the A82, A83 and A85 trunk roads, where lengthy closures as a result of accidents and crime scene investigations were a source of concern.

"The results of trials of these scanners in England have been encouraging and anything that can be done to reduce the time taken for crime scene investigations will be warmly received by my constituents," he said.