The announcement that Tom Harris is to seek the Scottish Labour leadership has led to calls for other Labour MPs to throw their hat into the ring. But it's also exposing a growing fact in our post devolution arrangements - there is more than one place to find political leadership.
Traditionally there has been a single source for a leader - the parliamentary chamber in question. It has been taken for granted that only a sitting MP/MSP/AM can contest the leadership and the loss of one's seat can be a near fatal setback for ambitions. But it's also led to the assumption that if someone leaves the chamber or politics altogether then they can't return and resume their ambitions.
That may have been a truism in times past, but we now live in an age where there are multiple parliaments and other positions. Is it really so wise to limit the choice of leader in a particular parliament merely to those who are currently members, and never consider talent that happens to be elsewhere?
And this goes beyond Westminster and the devolved parliaments. Why can't elected Mayors and council leaders be candidates for leadership? For that matter why not private citizens? Too often people complain about an insular political class - well here's a way that would allow people to dip in and out:
Allow anybody to contest the leadership of a party. If they're not an MP/MSP/AM etc... then they can either seek to enter the parliament in a by-election or await the next general election. A deputy can handle the parliamentary duties in the meantime and leave the leader with more time to tour the country. After all there's so much more to leading a political party than taking part in parliamentary questions.
This is not a novel idea by any means. Alex Salmond wasn't an MSP when he won the SNP leadership for the second time, and he didn't return to Holyrood for another three years. And outside the United Kingdom it's surprisingly common.
If Boris Johnson really has ambitions to be Prime Minister, he could do no worse than to watch the Liberal National Party in the Australian state of Queensland. Earlier this year the LNP picked as its new leader Campbell Newman, who is not an MP but rather the just stepped down elected Mayor of Brisbane, Australia's largest local authority. Newman is leading the LNP into the next election from outside the state parliament. If successful then Boris may want to pick up some tips.
Canada's tradition in this regard is far more advanced with both federal and provincial parties regularly picking leaders who are not sitting MPs, and it's common to find provincial leaders standing in federal leadership elections. Leaders who have not been sitting MPs when elected include Stephen Harper, Jean Chrétien and John Turner (all of whom were former MPs who had left parliament for industry but who then won their party leaderships), Jack Layton (who was a Toronto city councillor when elected to the NDP leadership), Brian Mulroney (a private businessman who had never held elected office before winning the Progressive Conservative leadership) and Robert Stanfield (who was Premier of Nova Scotia when elected to the federal Progressive Conservative leadership). There have even been Prime Ministers and state Premiers who have been appointed before being elected to the chamber - current Yukon premier Darrell Pasloski is not (yet) a member of the territorial assembly whilst British Colombia premier Christy Clark was sworn in in March despite not winning a seat in the legislature until May.
To the public at large it probably won't matter if a party's selected leader is an MP/MSP/AM or not. It certainly won't matter what precise title they hold. But it will be more problematic if a party is unclear about who their leader/"candidate for Prime/First Minister" is, leaving the media confused. Plaid Cymru found itself in this mess a few years ago before it changed its structures and what hasn't received much attention so far is that the post Tom Harris is standing for is technically only the leader of the Labour Party in the Scottish Parliament, a point that will be far more than pedantic in rows with MPs and councillors.
The other issue is getting the political and media culture to accept leaders who are not on the parliamentary benches, but time and precedent will accomplish that. Rival parties may mock a leader's "absence" but once they have done it themselves that line of attack will diminish.
Of course despite all of the above, Tom Harris is wrong to seek the Scottish Labour leadership for one very good reason. He is clearly in the wrong party!