I trawl political blogs quite often and one of the things I have noticed is the confidence of Coalition supporters that they can block any legislation for a carbon tax. A frequent refrain goes like this: “History tells us that it is virtually inevitable there will be a byelection during this term.” How does one explain the difference between their predictions and mine? My prediction is that there will be no federal byelection in the years 2011, 2012 or 2013. So let me set out some facts.

The last occasion there was a term of the House of Representatives without a byelection was in the 19th Parliament. That Parliament was elected on December 10, 1949. It first met on February 22, 1950 and was dissolved (double dissolution) on March 19, 1951. Consequently that term lasted one year and 25 days, making it the third shortest term in all our federal history. Every subsequent term has seen at least one byelection. The above facts would seem to suggest that these Coalition optimists are right. However, beginning with the  33rd Parliament (elected on March 5, 1983) there has been a pattern that suggests that my prediction is going to be proved correct.

I acknowledge an exceptional case. In the 39th Parliament (elected on November 10, 2001) there were two deaths in the House of Representatives. However, in the 33rd, 34th, 35th, 36th, 37th, 38th, 40th, 41st and 42nd Parliaments there was not a single death among the members of the lower house. In the list of terms named in the preceding sentence there were six byelections in the 33rd Parliament, one in the 34th, five in the 35th, two in the 36th, eight in the 37th, three in the 38th, one in the 40th, one in the 41st and five in the 42nd. That is 32 byelections, of which 31 were caused by the resignation of a member and one (Lindsay in October 1996) was caused by the Court of Disputed Returns upsetting the result at the general election earlier in the year.

I have followed the proceedings of our federal Parliament ever since April 1951 when the 20th Parliament was elected. During that Parliament there were 10 byelections, nine caused by the deaths of  members and one caused by a resignation. In other words there has been a sea change in the way parliamentary vacancies occur. These days vacancies are caused by resignation, not by death. This applies to all our parliaments and to upper houses as well as lower houses.

I live in the ACT and recently I was asked to give a talk to a local community organisation on the operation of our Hare-Clark system. So I did some research and discovered that there have been nine vacancies in the ACT Legislative Assembly since our first general election in 1989. All of those vacancies were caused by resignation, of which the most recent case was that of former Chief Minister, Jon Stanhope. At almost exactly the same time the first case of a vacancy occurred in the current term in Tasmania. Former Premier David Bartlett resigned from their House of Assembly. The count-back system gave each seat to another Labor member — without a byelection.

In New South Wales there have been three vacancies in the current term, all in the Legislative Council, all caused by the resignation of Labor members. In Victoria there has been one vacancy in the current term with a byelection caused by the resignation of former Premier, John Brumby. However, I shall not bore readers with the whole list. Every Australian parliament is the same. Vacancies occur often and they are always caused by resignation.

So politicians do not die these days. By contrast, up until about 1970 politicians did die and byelections  were typically caused by death. Why the change in pattern? The essential reason is the generosity these days of parliamentary superannuation schemes and the ease with which politicians get good jobs after leaving politics. In the past the typical politician expected to fail in the employment market post-politics. Since parliamentary salaries were good there was a great incentive for the politician to stay in his seat for as long as possible. Also medical advances mean that longer lives are now normal.

A current Labor member in any of about 40 federal lower house seats killed in a car crash would, of course, wreck the Gillard government. Surely Labor could not win a byelection in such a circumstance. However, such an occurrence is very unlikely. So what about a Labor member resigning his/her seat? Again, very unlikely.

The reason we have had so many byelections is that House of Representatives majorities for the government of the day have been large. In such a case, a party in power can afford a resignation. And opposition members could always justify a selfish resignation. For example, in the 42nd Parliament (2007 to 2010) three Liberal and two National former ministers resigned from their seats. In the process Mark Vaile gave away his seat of Lyne to Rob Oakeshott.

So I stick to my prediction. The 43rd Parliament (2010 to 2013) will be like the 19th. There will be no byelection. However, there will be an important difference. Whereas the 19th Parliament ran for just over a year, the 43rd Parliament will run for a full term of three years. The next general election will be in October 2013.