The history of attempts to reform the House of Lords has been a sorry one, amounting to more than a century of failure.

Despite appearing in the parliament act of 1911, introduced by a Liberal Government, no government has satisfactorily resolved the question.

One of the most recent concerted attempts, a white paper in 2007, offered seven options for change. All seven were rejected. A further attempt to secure backing for reform in the House of Commons, by the coalition Government in 2012, foundered amid a fiasco of party-politicking and and blame.

Senior sources now say the SNP is willing to back an American-style elected senate, which would give representation to the UK's nations and regions and replace the unelected House of Lords.

The suggestion is that this might be achievable, particularly in a scenario after the general election in which Labour wins, but needs the support of SNP MPs to enable it to govern.

The unelected second house has long been a bugbear of the SNP, which has always refused to sit in it, but reforming it was not a priority while independence remained a possibility prior to Scotland's referendum.

Now that outcome has receded for the foreseeable future, and the issue is firmly back on the party's agenda.

Reforming the House of Lords is on the agenda of the main parties too, but progress has stalled. It is timely for it to be revisited.

The plan for an elected senate of the nations and regions is likely to be included in Labour's manifesto, as the Herald reported last June. Gordon Brown proposed the idea in his recent book My Scotland Our Britain, published the same month. Mr Brown also spoke of the need for an elected second chamber, while making his famous Vow just before the independence referendum, when he proposed a new body which could act as the arbiter in disputes between the four nations of the UK. Ed Miliband, again prior to the independence vote, pledged to "change the British state, the House of Lords and the way we work together across our nations," if Scots voted No.

But leaving aside the politics of the referendum and the manouevring already underway to anticipate the possible outcome of May's Westminster elections, the need for reform is clear.

While it is no longer justifiable - if it ever was - to allow a body of unelected peers to scrutinise and reject the decisions of a democratic parliament, there are many other reasons why change is needed. The Lords are unrepresentative geographically, with their numbers weighted towards London. Those members from outside London are disproportionately rural. There remain concerns that many members still get there by patronage, often as a 'reward' for political support or donations.

At a time when public confidence in politics and politicians is at a worrying low, the House of Lords has become anachronistic. Worse than that, it has become emblematic of the kind of self-interest which turns people off politics. Ironically those of its members who resist change simply harden that view.

The SNPs initiative is therefore timely. We cannot know whether the party will be in a position after May 7th to negotiate on its senate plan.

However the party's shift is a timely reminder to all the parties and to voters of the need for the House of Lords to be changed, or completely replaced.