Yes campaigners are claiming the Westminster parties' timetable for further devolution is unconstitutional.
According to the research into the House of Lords, the unionist plans would need approval from voters in the rest of the UK.
A proposed timetable, setting out new powers for Holyrood in the event of a 'no' vote, has been agreed by the Conservatives, Labour and Liberal Democrats.
Kirkcaldy and Cowdenbeath MP Gordon Brown announced the plan, saying the Scottish Parliament should have wider over finance, welfare and taxation.
Excerpt from the House of Lords’ report:
1) The different constitutional outcome of “devolution max” requires a distinct constitutional process for its achievement. As illustrated by the potential for competing tax regimes within the United Kingdom, such an arrangement for one member of the Union would necessarily have real, deep and immediate consequences for the other members and for the Union as a whole. Properly to secure the legitimate interests of each and all, proposals as to “devolution max” would first have to be developed through intergovernmental negotiations conducted, not just bilaterally with the UK Government, but on an inclusive, multilateral basis across the Union state.
2) Whereas both the UK Government and the Scottish Government have recognised that independence is a Scottish question, “devolution max” is not. Proper constitutional process requires that negotiations involving all parts of the United Kingdom precede any referendum on an agreed scheme of “devolution max.”
Gordon MacIntyre-Kemp, CEO of Business for Scotland, said:
“Desperate last minute no campaign tactics have pushed Gordon Brown to the fore to announce a timetable for what they call ‘more powers in the event of a no vote.
“But this supposedly iron clad timetable does not include at any point a second referendum that allows for the people in the rest of the UK to vote on whether Scotland should be granted more powers.
“Let’s be clear, the House of Lords’ report states categorically that any further powers for Scotland should be subject to a UK -wide constitutional process, including the possibility of a UK-wide referendum. This means that the massive pool of MPs representing London and the South East, who benefit most from the union, effectively get a veto on whether or not to reform it.
“Ironically, just as honest attempts to reform the Westminster voting system and second chamber descended into dissatisfying fudge, so would further devolution for Scotland and Gordon Brown’s panicked announcement of an iron clad timetable disintegrate within days – much like most of the scare stories of the no camp.
“We can reasonably conclude that there can be no guarantee of more powers or any trust in the promises of the NO camp when the rest of the UK get to veto any offer. The timetable is not iron clad; it is shrouded in uncertainty. It is this very problem – 'that Devo max cannot be delivered at all' that led the Westminster parties to fight tooth and nail to keep it off the ballot paper."
At PMQs this week William Hague told the Commons that giving Scotland more powers if it does not vote for independence is not Government policy:
He said: "The statements by the party leaders made on this in the last few days are statements by party leaders in a campaign, not a statement of Government policy today but a statement of commitment from the three main political parties, akin to statements by party leaders in a general election campaign of what they intend to do afterwards".
"So it is clear it is not Government policy, no firm commitment has been made," added Mr MacIntyre-Kemp. “They say one thing to the people of Scotland and quite another at Westminster.