It happened on the A1 near Dunbar.
Third Of Top Police Could Retire By 2017
Almost a third of Scotland's senior police officers are eligible for retirement in the next two years, according to figures released by the Scottish Conservatives.
Of Police Scotland's 133 superintendents, 13% are eligible to retire in 2016, with a further 15% due for retirement the following year.
Among Scotland's 42 chief superintendents, more than a quarter could retire next year and a further 14% in 2017.
It means the organisation could lose 55 of its 175 most senior staff between now and 2017, said justice spokeswoman Margaret Mitchell, who called for assurances over recruitment from Scotland's top officer.
Phil Gormley will take up the role of Chief Constable of Police Scotland on January 5.
The former deputy director general of the UK's National Crime Agency succeeds Sir Stephen House, who stepped down at the start of December after Scotland's single force faced criticism over a number of incidents.
Ms Mitchell said: "I know first-hand from officers that the high turnover of senior management is causing continuity problems.
"Regrettably, based on the force's retirement projections these only seem set to continue over the next couple of years.
"We need assurances from the new chief constable that measures are in place to recruit suitably qualified replacements and provide much-needed stability for the rank-and-file.
"After a difficult two years, it deserves nothing less.''
A spokeswoman for the Scottish Police Authority (SPA) said: "The decision on when an officer decides to retire or move on is a personal one and it is not for the SPA to speculate in this regard. With responsibility for appointing Police Scotland's senior leadership team, succession planning is an ongoing piece of our work.
"This is informed by regular dialogue with our senior officers and our officers are required to give the SPA a three-month notice period.
"In addition, the SPA identified as a top priority the finding from the staff survey that one in three of the workforce would consider leaving Police Scotland within the next three years.
"The SPA and Police Scotland have made clear their determination to fully address the issues raised by staff and to engage with the workforce on what the solutions to those issues should be. That engagement exercise is well under way and will inform a comprehensive plan of action which will be set out early in the new year.''
The spokeswoman said that the SPA had secured the best candidate in Phil Gormley to build on progress made by Police Scotland and address challenges faced by the service.
A Scottish Government spokeswoman said: "We have delivered 1,000 additional officers compared to 2007, in stark contrast to the situation in England and Wales, where police officer numbers have fallen by over 15,000 (10.8%) from March 2007 to March 2015.
"The recruitment of senior officers is a matter for the Scottish Police Authority.''
The 26 year old was first targeted in Briarscroft Road.
Euan Johnston was shot in his car last month.
The family of three crash victims took their case for the 59-year-old to be put on trial to the Appeal Court in Edinburgh earlier this year.
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