Third power rule’s okay for the West

NOW that Attorney-General Jim McGinty and Greens MLC Dee Margetts have wrapped up their deal to boost the size of the Legislative Council from 34 to 36 members, it’s worth considering if WA has too many or too few MPs.

Coming to a conclusion on this prickly issue isn’t easy, as it can rapidly slump into a dispute involving subjective assertions and contentions.

But there’s a little-known measure that can serve as an enlightening prism through which to view WA’s parliamentary numbers.

It’s called The Cube Root Law (CRL) of Assembly Size, which postulates that: “The number of politicians equals the cube root of the size of the population”.

The word “law” here is used in the way economists apply it when discussing the so-called Law of Supply and Demand.

In other words, how people generally tend to behave in the economic marketplace.

The CRL, which applies to what may be dubbed the parliamentary marketplace, was first noted in 1909.

Nearly 80 years later, two Californian political scientists, Rein Taagepera and Matthew Shugart, have resurrected and refined it in their important study, “Seats and Votes: The Effects and Determinants of Electoral Systems.”

They’ve focused on an array of international legislatures and showed that their respective MP numbers tend towards being the cube root of the populations being represented.

And this is despite most politicians not knowing the difference between a cube root and any other root, for that matter.

Cubing a number, of course, means multiplying it by itself three times – for example, four cubed is 64.

It contends that, just as buyers and sellers behave predictably according to what’s called the Law of Supply and Demand, politicians worldwide have tended to set their numbers in legislatures according to the CRL.

So, if a population stood at a million, the CRL would predict there should be around 100 representatives, plus or minus a handful.

Taagepera and Shugart say MPs don’t deliberately act in accordance with the CRL.

Instead, it’s an unconscious process, stemming from, for want of a better term, their conscious predisposition to economising on work. Laziness is too strong a word.

Since retaining power is what motivates MPs above all else, each keeps a sharp eye out on the manoeuvrings of all fellow MPs and each closely monitors the mood and views of their voters.

Creating more MP spots means having to monitor more parliamentary manoeuvrings, but having commensurately fewer electors per MP, and vice versa.

But balances are struck between these two sets of full-time ongoing monitoring chores, and that tends to be reflected as the CRL ratio of MPs to populations.

It’s a fascinating observation of something that’s backed by statistics, so helps in grappling with the issue of whether there are too many politicians and offers a basis for assessing why particular numbers of MPs exists in given populations.

Certainly not all countries fall in-line precisely, but there’s a tendency to do so worldwide, even though a range of variations exist.

How’s all this relevant to contemporary WA?

Well, the CRL is uncannily on target for WA as things presently stand, if we combine the State and Federal MP contingents.

This certainly wasn’t always so.

WA’s population presently stands at 1.9 million and there are 91 State MPs – 15 House of Representatives and 12 Senators – so 118 all up which, when cubed, is 1.64 million.

For WA to be precisely on target to meet what the CRL postulates we would have 124 MPs, as that cubed is just over 1.9 million, our present population level.

And with the McGinty-Margetts deal set to lift MLC numbers to 36, WA will have 120 State and Federal MPs after the 2004 election.

However, things weren’t always skewed in the direction of too few MPs according to the CRL.

In 1901 WA, then a Cinderella State, had a huge 91 State and Federal MPs serving a population of just 185,000, meaning quite enough for a 750,000-strong population.

It wasn’t until the early 1970s – when WA’s population reached 1.1 million and there were 100 State and Federal MPs – that the CRL figure was close to the mark.

MP numbers have risen steadily since to the present 118, with 120 due in 2004, when the McGinty-Magetts deal takes effect.

However, we shouldn’t become too fixated over whether we have 118, 119 or 121 MPs since the CRL is an approximate rule of thumb.

The whole purpose of democratic government is to ensure voters and taxpayers are recipients of good governance.

It’s not there to maximise MPs’ comforts.

The crucial point is that there should be sufficient MPs in WA for them to institute an effective parliamentary committee system that inquires into and assesses emerging and ongoing issues confronting society so that government emerges with wise, workable, and cost-effective legislation.

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