A polarising debate around independence, the SNP embracing Nato & the Queen, Labour flip-flopping on tuition fees while toughening its stance on immigration and the Lib Dems continuing to find difficulty in balancing its principles with the reality of coalition Government are all contributing to perhaps the most turbulent period the political grass roots switching party identity in recent memory.

Despite the strict (some would say slavish) obedience to party lines within both of the UK’s Parliaments, it would not be altogether surprising if an MSP or MP had a quiet conversation with her or his self over the next few years and decided to defect to another party. It may be a hypothetical question for an issue that may never arise, but, in such circumstances, should the politician in question resign and fight a by-election under their new party colours?

There is no legal requirement to do so of course, but as the Jimmy Carr debacle has shown, that doesn’t necessarily make the rights or wrongs of a decision quite so clear cut.

More than ever before, elections are decided by the leaders at the helm of each party. The consistent swing from one party to another across the majority of constituencies at both Holyrood and Westminster is evidence enough of this. The SNP didn’t hammer Labour in constituency after constituency because they picked a raft of dazzling political individuals to stand as candidates, though I’m sure there are several in their number; it was because they had better policies as a party and Salmond appeared to make for a better FM than Iain Gray would have. They also had a massive spending warchest, but we don’t need to pick that old wound again.

So, the old adage that you could put a monkey in a red rosette in parts of Scotland and still win the election was brought to a swift end over the past year. I’m not even necessarily referring to the landslide victory in May 2011 here. After all, isn’t there a new adage? You could put an (alleged) wife-beater in an SNP rosette and still get him elected. Yes, that’s right, I went there…

The case of Bill Walker going from the SNP to an Independent MSP may be as close as we get to a defection at this parliamentary sitting. Nevertheless, it would be beneficial to have even an unofficially understood code of conduct around how any defections going forwards could take place. My particular bone of contention around this would protrude quite glaringly if Labour or the SNP (or whoever) were to accept an MSP or MP from a party after they had crossed the floor. If, as seems to be very much the case, the electorate vote for parties rather than people at the ballot box, is there not a moral duty for politicians, fed up with the party that got them elected, to resign and fight a by-election, if they wish to switch party?

For me, there absolutely is.

Perhaps there’s a clue from the first person to ever cross the floor at Westminster. In 1698, John Grubham Howe moved from the Whigs to the Tories. His nickname, I like to think… Howe Grubby.