theconversation.com/six-reasons-britains-impending-voter-id-law-is-a-bad-idea-196436
More worryingly, voter identification requirements lead to eligible citizens not casting their vote. It is difficult to calculate how many, but the voter ID pilots show that most poll workers encountered people who could not vote as they did not have ID. When photographic identification requirements were first introduced in Northern Ireland, it was estimated that 2.3% of the electorate were refused a vote for not presenting the required identification.
The government’s own research found that 4% of Great Britain’s population did not have photographic identification in which they were recognisable. That would mean that approximately 1.9 million people who are currently eligible to vote being excluded from elections.