Dilemma over England-specific laws
The Conservatives are making a play for English voters by saying there should be England-specific laws and taxes. But why is there is a discrepancy to fix and what are the proposals?
:: Where does this issue come from?
The so-called West Lothian Question was posed in 1977 by then Labour MP Tom Dayall. It highlights the dilemma of politicians from some parts of the UK taking part in Commons votes for laws which do not impact on their constituents.
The issue is particularly acute for Scottish MPs because of broad powers over domestic policy which are devolved to Holyrood, with more due to be handed over after the election whoever wins. Health, education and policing are looked after in Edinburgh - but Scottish MPs can still vote on Bills relating to these issues even though they only apply in England and Wales.
Decisions on public spending in England have tangential impacts in Scotland via the Barnett Formula, which determines the size of the grant from the Treasury to Scotland.
:: What are the powers in the different devolved assemblies?
The Scottish Parliament has powers over everything except a list of areas reserved to Westminster - this includes areas such as defence, foreign policy and broadcasting. The open-ended nature of the reserved powers system allows flexibility for policy-making by the Scottish Government.
In Cardiff, the Welsh Assembly has powers only in designated areas - making it much more limited. It can legislate in 20 areas, including health and education.
The Northern Ireland Assembly in Belfast has powers to legislate in designated "transferred areas".
The House of Commons remains technically sovereign over them all as their powers were created by Acts of Parliament and could be removed by the same mechanism.
:: How would the Conservative plans change the House of Commons?
The Conservatives, under plans drawn up by former foreign secretary William Hague, want to create a system where English MPs in the House of Commons get a veto over legislation that only affects England. A similar system would be created for legislation for England and Wales but not Scotland. The change would effectively add an extra stage to the legislative process in the Commons.
The Tories want this to include votes on income tax rate in England in the Budget, which more widely covers the whole of the UK. The Scottish Parliament is set to get tax setting powers under further devolution, and can already vary income tax rates, and the Tories say this should be matched for voters in England.
The Conservatives want to both change the law and change the rules in the House of Commons to make the plans a reality.
:: What are the arguments against making this change?
Labour has said the change would create two classes of MP at Westminster, which it opposes. It said all MPs should vote on key issues such as Budgets. It wants powers devolved to the cities and regions, and to reform the House of Lords instead.
Politically, a strong English votes for English laws rule could make governing difficult for a party holding lots of seats in Scotland - potentially rendering a majority government nationally a minority administration in England.
:: How long would change take?
The Tories want the plans to be in place before the next Budget, in March 2016. Proposed changes to Commons standing orders were published before Parliament broke up for the election.