Assuming big NO, a possible way to reorganise the Union
TLDR
- 4 National Parliaments to handle National matters
- National govs formed from the majority MPs in National Parliament
- 4 Parliaments come together (like a giant Power Ranger robot) to form the Union Parliament to handle Union matters
- Union gov formed from majority of MPs
- Tax raising powers and spending responsibilities are split between them
The Long Version
4 Nations, 1 Union
MP's are elected to represent constituencies as per now (or maybe another way). Ideally there are slightly more MP's per head for Scotland, NI and Wales than for England to give a slight counter balance to the population advantage of England.
Each nation has a parliament made up of the MP whose constituencies are in the nation. A national government (with First Minister etc) is formed by the majority party as per now. The national parliaments sit in the current national parliament/assembly seat. England may need a new English Parliament site, say Birmingham (based on it being big city in the middle).
All the MPs also represent their constituencies in the Union parliament (probably still in London). A Union government (with Prime Minister etc) is formed from the majority party in the Union. This may be a different party from the national govs and may be a coalition.
How it would work
The responsibilities and tax raising powers of the parliaments are divided.
To help I've included two pie charts from wikipedia, they are for slightly different years but it's indicative of the current gov spend/tax structure and it's the % I'm looking at. On the left is taxes, on the right spending
The Union parliment keeps all the responsibilities and tax powers it has now except for
- Income tax - 29%
- Corporation tax - 9%
Total tax rising powers of Union parliament = ~60% current
Total tax rising powers of National parliaments = ~40% current
The Union parliament is responsible for and pays for everything it does now except
- Education
- Social protection
- Transport*
Total spending commitments of the Union Parliament = ~60%
Total spending commitments of the National Parliaments = ~40%
*For large infrastructure projects, across nations, the Union parliament would be in charge, and the costs split in an agreed manner between the participating nations. So Heathrow expansion, would be out of English Parliament budget, A Rail line from London to Glasgow would be split between Scotland and England.
The reason I have left health care off the list (I could have had it in place of one of the others) is that I believe that the core healthcare across the Union should be uniform. Nations could do stuff (as Scotland already does) like subsidise prescriptions out of it's own pocket.
Although the National parliaments have responsibility for Education and Social protection, the Union would set down some basic standards, so all Union citizens will get certain things in Education and social protection guaranteed. The funds for these would come from central Union taxes.
This way, National Parliaments can set income tax levels and "curves" how they see fit, Scotland may have a more aggressive regime at the top end and tax corps and businesses more, whilst England could pursue a different regime.
All taxes would be collected by HMRC and then "block grants" to the national parliaments given, based on the take from their constituents.
So a person in England would pay all the same Union taxes (NI, VAT etc) that a person in Scotland would pay, but their tax code would be different (due to the income tax regime being different), so they might end up paying less (or more) tax.
When a person went to collect benefits, their place of residence (as determined by the electoral roll) would be used determine their benefits under the rules of the appropriate Nation i.e. registered as living in Scotland - pay Scottish taxes, get Scottish benefits.
Some problems
One of the disadvantages of this is that the MPs will have to wear two hats and be dashing back and forth between London and their National parliament. One possible solution to this would be to allow votes on Union matters to be cast either at London or at a National parliament.
This system may result in National and Union parliaments being opposed to one and other. Realistically speaking, England will tend to dominate the Union parliament, although with the tweaking of the number of MPs from the smaller nations this could be slightly counterbalanced. An additional counterbalance would be for some areas (e.g. use of Union troops outside the Union borders) to have a National government veto attached i.e. the vote is only passed if all 4 National Govs vote "yes".