His departure was swift, almost spectacular but whatever his reason Jason Ablewhite leaves office with Conservative Party colleagues across Cambridgeshire aghast.
Just six months before he was due to seek a further four year term (he was re-selected as far back as February), Mr Ablewhite vacates both the office and his £85,000 a year salary.
For now, seemingly, he remains a Huntingdonshire district councillor for St Ives (allowance £4,500 a year) but his ambition to serve a second term as police commissioner is out of the window.
Senior Conservative officials were notified on Sunday of developments within the office of the police and crime commissioner ahead of today's brief statement.
The statement says that Mr Ablewhite has been referred to the Independent Office for Police Conduct (IOPC).
"Jason Ablewhite has today (Monday November 11) tendered his resignation as Police and Crime Commissioner for Cambridgeshire and Peterborough.
"It would be inappropriate for us to make any further comment."
In February he was re-selected by his party to contest the 2020 Police and Crime Commissioner elections in Cambridgeshire at a meeting of members in St Ives.
Mr Ablewhite was first elected in May 2016 to succeed Sir Graham Bright and at his re-selection meeting he was confirmed as the choice for 2020 in a secret ballot of members.
His leadership has, at times, proven fractious and he has been heavily criticised by many for his desire to use a new Government policy to take control of Cambridgeshire Fire and Rescue. Persistent legal challenges by the fire authority have put that plan on hold and it now remains uncertain if it can go ahead.
"It is a huge privilege and an honour to have the continued support of Conservative members in Cambridgeshire," Mr Ablewhite said after being re-selected.
"Being the police and crime commissioner has been one of the most fulfilling and fascinating roles of my life.
"I am delighted to commit myself to the campaign ahead and ensure we continue to protect frontline policing while coming together across the public sector to support and protect vulnerable victims of crime".
His career in politics spans many years, having been a ward councillor for St Ives for 17 years. Prior to taking on the PPC role he spent five years as executive leader of Huntingdonshire District Council and is a former mayor of St Ives.
At the 2016 election - for which there was a 30.56 per cent turn out - he emerged victorious after two rounds of vote with a 9,371-vote majority over his nearest challenger, Labour's Dave Baigent, after second preference votes were taken into account.
Mr Baigent contested the second round of voting against Mr Ablewhite after polling 54,426 votes in the first round.
And, although he picked up more second preference votes, it wasn't enough to close the gap on Mr Ablewhite.
UKIP's Nick Clarke (29,968) and Liberal Democrat Rupert Moss-Eccardt (27,884) were both eliminated after the first round of voting.
Cambridge City Council leader Lewis Herbert tonight tweeted; "Not defensible for any public official to resign without explaining why.
"Particularly the Cambridgeshire and Peterborough Police and Crime Commissioner, in charge of policing. "And will the area now be without police accountability for nearly six months, until the full elections?"
District councillor Aidan Van de Weyer said that had Mr Ablewhite resigned five days earlier there would have been a by election.
"Did he hold off resigning to avoid a by election?" he said.
Social media tonight is awash with speculation and some senior politicians are already distancing themselves from Mr Ablewhite.
Tory Party chairman James Cleverley has discovered that a retweet he made two months ago from Peterborough Tory candidate Paul Bristow has been deleted.
Mr Cleverley had described it as "brilliant" joining Mr Ablewhite and Mr Bristow on a visit to Central Park, Peterborough.
It could be sometime before details of the allegation against Mr Ablewhite become public knowledge.
An IOPC spokesman said: "The IOPC has started an independent investigation following a referral about a public complaint into the conduct of the police and crime commissioner for Cambridgeshire.
"We are in the process of gathering and evaluating evidence and do not want to pre-empt investigative decisions."
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