Dr Renwick:

Both of the principles that you have just mentioned matter, and so does the principle that there should not be too much chopping and changing of constituency boundaries from election to election. There is no single correct answer to the question of how those different principles should be balanced. The Venice Commission from the Council of Europe recommends a maximum deviation from perfect equality in numerical terms of 10%. Currently, under the UK rules we have 5%. The evidence from Charles Pattie and David Rossiter, which I am sure you will hear this afternoon, suggests that something like a deviation of 8% would allow much greater account to be taken of local community ties and much less chopping and changing between elections.