With local authority elections due in May, Allan Urry investigates claims of organised vote rigging. Earlier this year, the Electoral Commission identified 16 areas in England with wards that are at particular risk of electoral fraud. File on 4 visits some of those towns and cities and hears first hand evidence of intimidation and the widespread abuse of postal votes - including allegations that some people are being pressured into handing over their vote to party activists. A candidate who successfully took a court case against his opponent after narrowly losing an election, says some campaigners have lost sight of what is right and wrong. And a judge who sits in election fraud cases attacks the system as "shambolic" and "wide open to abuse". So is our voting system too vulnerable to fraud? Are the authorities doing all they can to root out corruptions? And is it time to end postal voting on demand? Producers: Emma Forde and Sally Chesworth.