One of the curiosities of the parliamentary system is that governments can find themselves hostage to the vagaries of members’ personal fortunes. This was the unhappy lot of Julia Gillard’s government after the 2010 federal election, when the destiny of the nation at times seemed to hinge upon seedy text messages and credit card receipts from houses of ill repute.

A very different manifestation of the phenomenon is playing out in South Australia, following the death on Saturday of independent MP Bob Such.

Such was unquestionably a popular figure, not least among his constituents, who re-elected him as an independent four times between 2002 and 2014 by margins of between 9.4% and 16.7%.

No one can doubt that the tributes being paid to Such from across the political spectrum are heartfelt. But at the same time, those with a stake in the state’s politics will not be losing sight of the fact that the Such’s passing, which was sadly not unexpected, creates a vacancy in his southern Adelaide seat of Fisher that will shortly be filled through a byelection.

Such emerged from the election on March 15 as one of two independents in a hung Parliament, the other being Geoff Brock, who won re-election to his Port Pirie-region seat of Frome. Of the remaining 45 seats in the lower house, Premier Jay Weatherill’s Labor government retained 23 — a better return than it had a right to, given the 53-47 advantage to the Liberals on the statewide two-party vote.

Labor’s one-seat advantage over the Liberals was always going to give it the whip hand in post-election negotiations with the independents, as any minority Liberal government would have been reliant on the casting vote of the Speaker. However, the point was rendered redundant when Such took extended sick leave a week after the election, revealing shortly afterwards that he was receiving treatment for a brain tumour. With Such’s vote out of the equation, the choice facing Brock was not between Labor and Liberal, but Labor and deadlock.

As Liberals nursed their outrage at a second successive failure to take government despite outperforming Labor on the aggregate vote, further salt was applied to the wound by one of their own. Martin Hamilton-Smith, a former party leader of long-stymied ambition, took a shortcut to ministerial office through an accommodation with the government, which received a 24th vote on the floor in exchange for a cabinet post for Hamilton-Smith as Investment, Trade, Defence Industries and Veterans Affairs Minister.

“It’s not often that governments gain swings at byelections, but there is some cause for the Liberals to fear that this might be one of the exceptions.”

To this point, the Liberals had cause to be keep a morbid eye on Such’s temporarily vacated parliamentary seat. Were the Liberals to recover it, the potential existed for Brock, whose electorate is broadly conservative, to have second thoughts about supporting Labor in government. But the loss of Hamilton-Smith pushed that prospect one seat further away.

While the byelection in Fisher does not loom as an immediate matter of life and death for the Weatherill government, a Liberal win would at least return it to the being a few “acts of fate” away from losing the parliamentary numbers. That would seem to be the most likely outcome in a seat that has only once been won by Labor in a history going back to 1970, Bob Such having held it for the Liberals from 1989 until he resigned from the party in 2000.

However, Fisher is certainly not that safe that the Liberals can afford to be complacent. If vote patterns from last year’s federal election were replicated in the seat, their margin would be barely over 2%.

It’s not often that governments gain swings at byelections, but there is some cause for the Liberals to fear that this might be one of the exceptions. The latest quarterly state result from Newspoll, published in The Australian a fortnight ago, suggested that yet another electoral failure had badly dented the party’s credibility in the eyes of voters. Furthermore, Labor will be able to plead that an extra seat for it in parliament will grant the state greater stability and certainty. Failing that, there remains the possibility that the electorate has not lost its taste for independent representation.

The necessity for a byelection in Fisher also focuses attention upon Liberal warhorse Iain Evans, who announced in June that he would retire from Parliament at an indeterminate point over the coming 12 months. It would be opportune if he were to time his departure to allow for simultaneous byelections in Fisher and his Adelaide Hills seat of Davenport. Davenport is not a prospect for Labor, but the Adelaide Hills area it covers has often shown independence of mind, having once been a hotspot of support for the Australian Democrats.

Furthermore, there were suggestions earlier in the year that Evans might prove the tip of an iceberg of Liberal resignations, potentially encompassing as many as four more lower house MPs.

While this was painted by Liberal sources as an opportunity for renewal, the resulting byelections would also entail danger for Liberal Leader Steven Marshall. Little credit would accrue to him from achieving the mundane feat of retaining seats at byelections from opposition. However, any unexpected mishaps could weaken him in the eyes of his already dispirited and impatient colleagues.