Tory ministers are set to scrap the voting system for key local elections in a move that has left reform campaigners dejected.
Until now, police commissioners, metro mayors and the London mayor were some of the only public offices not elected through the "first past the post" system.
Instead they used the "supplementary vote", where a candidate can only win once they have at least 50% of voters' support including second and third preferences.
This second-preference system is designed to ensure no one can take office with a support of only 30% or 40% of those who voted.
That was seen as especially important in police commissioner elections - for which turnout was just 27% in 2016.
But now they will return to the winner-takes-all "first-past-the-post" procedure, just like in Westminster elections, under plans by top Tory Priti Patel.
She said the change - which will not affect this May's local elections - will "provide for strong and clear local accountability" and was backed up by the Tories' 2019 manifesto.
But the Electoral Reform Society said first past the post was a "broken" system that could allow police commissioners to "sneak" into office with only a sliver of public support.
While it would not have dramatically changed police commissioner results in 2016, critics say first-past-the-post denies minority parties or independents a shot at high office, especially in Westminster.
Senior Director Willie Sullivan said: "Imposing Westminster’s broken first past the post voting system on the Mayor of London and mayoral and PCC elections across the UK is a step backwards.
"[It] would see multi-million-pound budgets handed to people the majority of voters don’t want - damaging accountability and undermining the legitimacy of those elected.
"Offering voters a second preference using the Supplementary Vote acts as a safeguard against future mayors sneaking into city and town halls on low levels of support by ensuring the winning candidate has a broad backing of voters - vital for officials with wide-ranging powers over policing and crime in our local communities.
"With all the challenges facing the country right now, making it easier for unpopular candidates to win mayoral elections should not even be in the government's to-do list
"We need to be finding ways of increasing accountability for our politicians, improving our democracy and making it fit for the modern age instead of turning back the clock and adopting a discredited, outdated and broken voting system."
Ms Patel said: “Police and Crime Commissioners play a crucial role as the elected voice of the people for crime and policing, which is why I am committed to ensuring they are accountable to the communities they serve and are strong, visible leaders in the fight against crime."
