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Chief Constable Andy Marsh has announced he will step down from the role when his contract expires this summer.
CC Marsh said it has been the “honour of a lifetime” to lead the force he first joined as a new recruit in 1987.
After starting at Avon and Somerset Police, CC Marsh took on both operational and detective roles up to the role of Chief Superintendent and BCU Commander, first for South Bristol and then Somerset East.
He went on to serve as Assistant Chief Constable at Wiltshire Police and then Avon and Somerset Police, before being appointed Deputy Chief Constable and then Chief Constable at Hampshire Police and then taking on the Chief Constable role at Avon and Somerset Police in February 2016.
CC Marsh said: “To leave a force I first joined in 1987 has been a difficult decision to make, but I feel it is the right time for me to embark on a new challenge and for another person to take the helm and continue on the journey to make Avon and Somerset Police the outstanding force it deserves to be.
“It’s been the honour of a lifetime to lead a force filled with officers, staff and volunteers who live and breathe our values of being a caring, courageous, inclusive and a learning-led organisation.
"I’m very proud of their achievements and the work they do every day to serve and protect the public.
“Along with society, the world of policing has undergone a seismic shift since I joined in the late 1980s in terms of culture, attitude and professionalism, and from my role as NPCC lead for international policing, I know our model of policing remains very much the envy of the world.
“On reflection, I’ll take great pride in the trail-blazing advances the force has made in equipping our officers and staff with the best technology in the world, helping us to become more agile and data driven in investigating and disrupting crime, safeguarding and protecting victims and identifying those who pose the greatest risk of harm.
“We need to stay ahead of the curve when it comes to embracing new technology and we’re already a leading force developing robotics and automation. Policing will of course always be about people, and our vision, leadership and operationalisation of the opportunities offered by digital, technology and data will keep this force at the leading edge.
“Avon and Somerset Police has been at the forefront of these developments and I am proud of what we have achieved during my time as Chief.
“The Avon and Somerset area has wonderfully rich diversity, strong communities and an enduring sense of public spirit, which will only make it an even harder wrench to leave my role this summer.”