Winter elections to appoint the first police commissioners in England and Wales will be a "complete shambles", campaigners warn.
Fewer than one in five voters are expected to turn out for the November 15 ballot, according to the Electoral Reform Society.
It warned the possibility of just 18.5% of eligible adults taking part could give an unfair advantage to extremist candidates who would otherwise have little chance of success.
Katie Ghose, Electoral Reform Society chief executive, said: "This election is beginning to look like a perfect storm, which could result in the lowest turnout for a national election in British history.
"Those pulling the strings have not done their homework and as a result this election looks primed to degenerate into a complete shambles. Put simply, if the people elected to localise decision-making over how our streets are policed, do not represent local people, what is the point of having them?"
Baroness Angela Smith, shadow home office minister, said: "We warned Theresa May time and again that spending over £100 million on these elections at a time when she has already cut 10,000 police officers from the streets makes little sense and should not be the priority.
"We also warned against holding these elections in November, risking an extremely low turnout. Now we hear it may be historically low.
"The Home Office and Theresa May are once more in a mess of their own making. Understandably they are embarrassed, but they need to get a grip and make the best of a bad job. That's what we are trying to do across the country as we campaign against the Government's huge cuts to frontline police."
A Home Office spokesman said: "Police and crime commissioners will, unlike invisible and unelected police authorities, give local communities a say over policing priorities in their areas and work with the police to cut crime."