Constituency boundaries will dominate the proceedings in the Commons today. Labour are bringing forward a Bill which would have the effect of scrapping the current proposals and effectively starting again. Instead of 600 constituencies there would continue to be 650. The variation in sizes allowed would increase from 10% to 20%. We have already seen with the present boundary commission proposals how controversial changes to boundaries can be but I think one thing most people agree on is that the current variances between constituency sizes are difficult to defend.