Turnbull's lament on the degradation of our politics is justified, but prescribing a solution is more difficult.
FOR the second time in two months, Malcolm Turnbull has delivered an original, thought-provoking contribution to the public debate, the like of which we too seldom see from our politicians.
His earlier lecture was a compelling plea in favour of legalising gay marriage; on Wednesday he addressed the issues of truth, trust and the general degradation of our politics.
Inevitably, his remarks would be seen as a poke in Tony Abbott's eye, whether intended or not. Probably not a day goes by that Turnbull doesn't wonder how it is that Abbott, not he, is the Liberal leader. It would be no comfort that he knows the answer - he could not keep his team's support when he had the job. But let's take Turnbull's propositions on their merits regardless of motive.
He argues that the public deserves an honest and quality discourse, but the political system is skewed to encouraging ''spin, exaggeration, misstatements''. Discussion on complex and important issues is distorted or worse; not surprisingly - it brought him down - Turnbull points to the ''hopeless, confused, hyper-partisan'' debate on climate change.
With the opposition, shock jocks and others throwing charges of ''liar'' at Julia Gillard, Turnbull probes the anatomy of a political lie.
''A lie is a false statement known to be false by the person who utters it,'' he says. ''A change of policy is not a lie. If a politician says the best policy to promote innovation is ABC, and then comes to the view that it is in fact XYZ and says so, he is not telling a lie, he is changing his mind - unless of course he never believed ABC was the best policy in the first place.''
Where does this leave Gillard for her notorious pre-election ''there will be no carbon tax'' promise? Off the hook? Not on Turnbull's argument, because she is guilty of a ''breach of contract''.
Turnbull's analysis of our political system's faults and the public's resulting cynicism seems to me entirely spot on. But prescribing solutions is much more difficult.
Take his slating of question time, which he says arouses fury and contempt, pointing out that for the past two years opposition questions ''have been almost entirely focused on people smuggling and the carbon tax''. Turnbull is right about the inanity, but would his answer make things better? He suggests a British-type model, where the prime minister takes questions only on a certain day, so ministers are the centre of attention on other days.
That system has its advantages - we would, for example, probably get to know more about low-level scandals in a whole range of departments. But our system of an ever-present PM has its strengths too; if a big issue suddenly arises, and Parliament is sitting, the prime minister can be questioned immediately.
It should be remembered, too, that we've already tried a version of the British system: Paul Keating restricted the times he attended question time - the arrangement was not thought a great success.
Turnbull admits he doesn't have ''any silver bullet to make us politicians more accurate or more likely to keep our promises'', while urging them to earn trust by refraining from raising false expectations and misrepresenting their opponents.
The adversarial system is at the heart of our democracy. But when it starts to undermine some democratic values, when politicians can seldom co-operate or recognise the other side's better selves, it results in dangerous voter alienation - which is also being seen in other Western democracies.
As former US president Bill Clinton, addressing the Democratic National Congress, said yesterday: ''When times are tough, constant conflict may be good politics, but in the real world co-operation works better. After all, nobody's right all the time, and a broken clock is right twice a day.''
There is much reason for disillusionment with the current state of politics in Australia. But as a slight cheer-up, remember a couple of counterpoints.
The intense, sustained conflict of the hung parliament is a specially nasty period to watch - constant warfare has brought out the worst in many players.
Second, sometimes the bad can actually act as an incentive for good. Politicians don't react to appeals to behave better, but if bad conduct brings pain then they take notice. Gillard's trashing over the carbon pledge is likely (at least for a while) to be something of a deterrent to others.
Apart from its dissertation on political discourse, Turnbull's speech is notable for drawing attention to how the contraction in the mainstream media will affect reporting on politics (''There are just as many political foxes, but a lot less journalistic hounds to keep an eye on them'') and for his latest observations on an Australian republic.
On the latter, he has started to think that an elected president - a model he so trenchantly opposed but the only one likely to get public support - might just possibly work satisfactorily. It's an interesting evolution for one of the nation's most significant republicans, in the event that a new round of that debate comes in the next few years.
Michelle Grattan is The Age's political editor.