There have been important changes since the three 1998 devolution Acts: the oft-used term "devolution settlement" masks a reality of tension and adjustment.
The Scotland Act 2012 devolved important tax-raising powers which will become 'live' in 2015 and 2016. In Wales three distinct models of devolution have been used, two under the Government of Wales Act 2006, including a shift to full primary law-making powers over specified matters after a referendum in 2011.
Fiscal devolution is provided for in the Wales Act 2014. Northern Ireland has had several alterations including in particular the Northern Ireland (St Andrews Agreement) Act 2006 and the Justice and Security (Northern Ireland) Act 2007.
The 2015 Parliament convenes at a time of ongoing change, some foreseeable, some in the form of less predictable interactions and consequences.
Before the Scottish independence referendum in September 2014, as opinion polls narrowed, the three main UK parties made a "Vow" to devolve significant new powers to Scotland. They committed themselves publicly to a timetable for further devolution, and set up a Commission under Lord Smith of Kelvin to broker an Agreement.
This led to a set of draft clauses put forward by the Government as the bones of a Scotland Bill that might be introduced in the new Parliament.
The clauses included statements that the Scottish Parliament is recognised as permanent, and that the Sewel Convention, whereby the UK Parliament seeks consent before legislating on devolved matters, is recognised in statute.
They included new fiscal powers, including to create new bands and rates of income tax, some devolution of welfare, the licensing of fracking, and the running of the Crown Estate in Scotland.
None of this binds the incoming Parliament. However, there is a strong political commitment to further devolution for Scotland. While the draft Clauses might be rewritten, legislation reflecting the Smith Commission Agreement will be needed if Unionists are to avoid accusations of seeking to influence voters in the referendum with promises they failed to deliver.
Devolution in Wales has been modified several times. Most recently, there is provision for tax raising powers in the Wales Act 2014, which would come into effect if supported in a referendum.
The previous Government sought to achieve cross-party consensus on new arrangements for taking devolution forward after the general election. This was published in February 2015 as Powers for a Purpose, also known as the St David’s Day Agreement.
Among other things, this would change the devolution model in Wales to the reserved powers model used for Scotland, a move favoured by the Welsh Government. This tends to be a more permissive approach, as only those powers which are explicitly reserved in the Act are kept at the UK level: everything else is presumed to be devolved.
In addition, the current Welsh Government has argued that progress should be made towards an eventual separate legal jurisdiction. At present, England and Wales form a single jurisdiction, but as the Welsh Assembly passes its own laws, the law effective in the two countries becomes dissimilar.
There are reports that this already creates difficulties for solicitors representing clients based in England who are involved in legal processes in Wales. To the extent that practical differences become pronounced and widespread, pressure may grow for formal separation.
The arrangements in Northern Ireland have also changed over time, though for different reasons. The UK and Irish Governments held talks with Northern Irish political parties in December 2014 to deal with outstanding issues concerning flags, parades and the past, and a desire by Sinn Fein to soften the impact of UK welfare changes in a way that put pressure on the budgetary arrangements.
These led to the Stormont House Agreement, which included a package of financial support from the UK, devolution of corporation tax, and new processes for dealing with flags, parades and the past. How that Agreement plays out over the coming months and years will weigh on the success of Northern Ireland's devolution in the next period.
Are we nearly there yet?
The changes in Scotland will create anomalies elsewhere in the UK unless there is additional legislation for Wales and Northern Ireland.
For instance, it would seem odd to put the Sewel Convention on a statutory footing for Scotland but not for Wales and Northern Ireland. To the extent that Scotland has provided a vanguard for devolution, increased autonomy there creates a new limit case.
Just as Wales is on the verge of moving to a Scottish-style model, further developments in Scotland could leave Wales behind again. Advocates of asymmetry might argue that there is no inevitable link between the arrangements in Scotland and Wales, but in practice some influence is felt.
The situation in Northern Ireland is affected by a range of complex considerations, but it may not be entirely cocooned from developments elsewhere.
- Conservatives: will continue devolution settlements for Scotland and Wales, and implement the Stormont House Agreement in Northern Ireland.
- Greens: will consider further devolution to Scotland, Northern Ireland and Wales
- Labour: meet promises to devolve further powers to Scotland and Wales
- Liberal Democrats: implement home rule powers as proposed by the Smith Commission in Scotland and will complete comprehensive devolution to Wales and Northern Ireland
- SNP: welcome the proposals set out in the Smith Commission but argue that "the package, as it stands, does not enable us to deliver fully either the greater social justice or the powerhouse economy that our country demands"