If there is a turning point in the Australian debate on same-sex marriage it may well be Penny Wong’s remarkable grace and honesty when answering Joe Hockey on last night’s Q&A.

Wong was asked by host Tony Jones whether Hockey’s view that children were better off with a mother and father was hurtful to her.

“Of course it is,” she said. Then, with a curt nod: “But I know what my family is worth.”

For once, a minister spoke on television from her heart, unconstrained by the need to follow whatever script was issued that day from head office.

But such honesty is rare in political debate in Australia.

Recently I appeared on an ABC program called, ironically, “Outsiders”. Ironic because one of my co-panellists was former Liberal Minister Peter Reith. Whatever else one might say about Reith, he is not an outsider, and he obediently repeated the current Liberal Party attacks on the government.

The trend towards employing ex-politicians to pontificate is increasing at an alarming rate. The Age gives us the reflections of Amanda Vanstone and Peter Costello on a regular basis. Mark Latham seems to be embedded in the Financial Review, and Graham Richardson is such a fixture on Q & A that he is presumably now entered as a depreciation for tax purposes.

Latham and Richardson can at least be counted on for venom, passing as analysis. Costello and Vanstone, being somewhat more loyal to their old mates — well, not all of them in Costello’s case — will tell us, predictably, the current party line.

Other than a moment from Malcolm Fraser some years ago, acknowledging during a speech at La Trobe that he had not handled East Timor’s independence movement well, I have yet to hear a former politician admit to an error, or add much to political understanding. But this is symptomatic of the general decline of political commentary, which becomes increasingly an obsessive rehashing of current events, in which predictable positions are adopted.

If it isn’t politicians, we rely on members of the press gallery, who between them dominate political analysis on Sunday morning talk shows. I suspect no one watches these shows, but they provide footage for the evening news, when the same opinions that were in their newspapers can be trotted out again, and then reported the following day in an endless cycle of repetitive insider knowledge.

There are some dispassionate political journalists: George Megalogenis continues to actually analyse rather than preach, as did Michelle Grattan before her extraordinary dislike of Julia Gillard took over. But the cycle of the same small group of folk reinforcing each others’ views is drowning out anything else.

Until politicians are free to actually express their own views rather than those of the party, they cannot be used as commentators. Perhaps that is why the final exchange between Penny Wong and Joe Hockey on Monday’s Q&A was so electric. Here were current politicians talking about personal beliefs, and Hockey’s clear embarrassment was evidence that his basic decency is restricted by his party’s policy.

Far more important than Gillard’s rather inexplicable opposition to changing the Marriage Act is that the Liberal Party, which claims to believe in individual conscience, has forbidden a free vote on the issue. Australian politics is remarkably restricted by party discipline, which means that what passes for debate is limited to who can be most ingenious in finding ways of selling statements they obviously cannot believe.

Frontbenchers have to defend party policy. I don’t expect Wong to agree that the surplus is a con job or Hockey to acknowledge that his knowledge of economics is sadly limited. Their job is to be combatants, though one wishes their language could be as dignified as Wong was on Monday. But we desperately need commentators whose positions are not compromised by partisan loyalties, or the need to exercise payback.

We used to rely on the ABC for this sort of informed but dispassionate analysis. Maybe it’s time for it to cleanse its stables and move beyond the smug circle whereby “insiders” and “outsiders” merge, as long as Tony Jones can interrupt at will.