HUDDERSFIELD MP Barry Sheerman has demanded an inquiry into why thousands of people have dropped off the voting register.
Six thousand fewer names are on his constituency's list than in 1995.
The 9.1% drop is one of the largest in the country, said Mr Sheerman.
He said: "I want to know why. It's not as if the population has dropped."
The Labour MP said he had raised the issue in July last year, but it had not been taken seriously.
He added: "I have been contacted by numerous people who have been disenfranchised. I am seriously concerned that this seriously undermines the democratic process.
"I am demanding an explanation for why so little has been done. I want to see an immediate action plan from Kirklees Council."
A council spokesman said the Government was now demanding that electoral registers be published in a shorter time.
He said: "Previously, they had to be available by mid-February, but the date has now changed to the beginning of December.
"We have also been required by the Government to remove the names of people who do not respond for two years to registration papers that are sent out."