David Cameron recently said that being forced to give prisoners the vote made him "physically ill" and he is likely to be feeling even queasier today.
The news that 28,770 prisoners will be given the right to vote, including 5,991 prisoners convicted of violent offences and 1,753 inmates convicted of sexual offences, has inflamed the Tory right and the tabloids.
It has also provided Labour with an opportunity to attack the Tories from the right for the first time since Ed Miliband became leader. The shadow justice secretary, Sadiq Khan, who served as Miliband's campaign manager during the leadership election, said:
This is a slap in the face for victims of crime. We have already seen the Conservative-led government break their promise on knife crime. Now they are also giving thousands of offenders the vote.
MPs on all sides of the House and the public are right to be angry about this decision. But they should also be angry at the manner in which it was announced – sneaked out on the day parliament broke up for Christmas.
Labour now has a chance to outflank the Tories on this emotive issue and to form a tactical alliance with Conservative backbenchers, as many as 40 of whom are prepared to vote against the government.
The party plans to table a smart amendment restricting the right to vote to prisoners serving up to one year in jail. Under the coalition's plans, all prisoners serving up to four years will win the vote, including sex offenders. It is this that has so aggravated the Tory back benches. The government is legally required by the European Court of Human Rights to end the blanket ban on prisoners but it is still free to set its own limit.
One of the Tory rebels, Philip Davies, tweeted today: "Outrageous stats today show 28,770 prisoners would be given the vote – including 6,000 violent offenders and 1,700 sex offenders!"
Under Labour's plan, these prisoners, who typically serve sentences of more than a year, would be barred from voting. Several Tory MPs including Davies have already pledged to vote for the opposition amendment.
If he wants to avoid his first Commons defeat, Cameron would be wise to back down and agree to a one-year limit. After U-turns on free milk, school sports and, most recently, Bookstart, it looks like prisoners' votes will be next.