If bookmakers and polls are still be trusted, Andy Burnham is favourite to become Ed Miliband's successor as leader of the Labour Party.

As such, the Shadow Secretary for State for Health (for England) might feel entitled to declare there is "a case" for separate parties north and south of the Border. It is not self-evident Mr Burnham has such a right.

That said, it is no longer obvious why Jim Murphy is entitled to award himself a month in the Scottish leader's job while he prepares a plan for reform. Which successor could agree to be bound by such a blueprint? What credibility still attaches to Mr Murphy, who talked a good game, lost 40 of 41 MPs, and won the confidence of the party's Scottish Executive thanks to his own vote and the backing, it seems, of Baroness Ramsay of Cartvale, a late addition to the squad?

Who does speak for Labour in Scotland? Many, led by Mr Murphy, would baulk at the idea of Len McCluskey, general secretary of the Unite union, as arbiter. Nevertheless, the lack of one-person, one vote in the affairs of the Scottish party still allows unions an undue say. Mr McCluskey is another with dubious credentials as a kingmaker, but he is not first on the list of the party's problems.

For Labour, in Scotland and beyond, an almighty, enveloping mess threatens to descend into tribal warfare. Blairites, Brownites, modernisers, traditionalists, left, right: it is easier to say what divides those loyal to the red rose than what unites them. The question of what becomes of the party in Scotland is deeply serious, yet answers are few. Those with the authority to speak have yet to be found.

Mr Burnham - and he is not alone - seems to be turning his back on a Scottish problem in pursuit of votes elsewhere. Talking on the BBC's Andrew Marr Show yesterday, he had few details to offer of "the case" for an autonomous party in Scotland, whether the relationship would be formal or informal, or what this could one day mean for devolved government. Inadvertently, he raised the question of legitimacy. For whom does he speak when he notes that "case"?

Mr Murphy and Mr McCluskey seem to be happier squabbling, for now. No doubt they could explain the reasons at length. Very few voters are liable to spend much time on such feuds. One cavils, the other carps, and Mr Burnham pretends to understand while conducting an entirely separate leadership campaign. Even a terrible election for Labour should not have reduced the party to this condition.

Why should it matter? After all, across the United Kingdom, Labour is a beaten party. In Scotland, it could not muster even a quarter of the votes cast. But this remains the official Opposition at Westminster and at Holyrood. With a minority government in London showing its colours, and with an SNP administration in Edinburgh resembling an electoral steamroller, democracy requires a coherent opposition. A summer of internecine Labour warfare will not meet the need.

For the party, the alternative is noisy irrelevance while once-minor rivals attempt to fill the vacuum. None is entirely plausible, as yet. The fact underlines the responsibility falling on those who claim the right to speak without having earned their right.