Last week, erstwhile PM Tony Abbott tried and failed — again — to pass the “Warringah motion”, which would grant more control over preselections to rank-and-file New South Wales Liberal Party members. Much of the media reporting on the issue focused on the key players, but missed some of the politics, before disappearing entirely under the Barnaby Joyce saga.

The Warringah motion is most commonly spruiked as a way to ensure greater democracy within the Liberal Party by taking a one-member, one-vote approach to preselections. The idea is to give party members in a given seat, a vote in each preselection for that seat, and to give members across the state a vote in upper house preselection. Instead, a compromise “Bennelong motion” was passed, which granted party members some control of lower house preselection, despite the criticism of at least one minister. While newly installed Senator Jim Molan was “personally disappointed”, Abbott struck a slightly disingenuous note  in “urging members not to quit over the loss”.

As things stood prior to the weekend before last, Liberal Party state council, state executive and branch delegates determined preselections. With a compromise done, shepherded through by moderate Matt Kean and hard-right NSW Deputy Liberal Leader Dominic Perrottet, peace seems set to return, at least until the next time Abbott and key allies press on again.

It’s hard to escape the view that one of the reasons Abbott and his allies are so keen on such motions is their (likely correct) assessment it would return more conservative candidates. The logic that these party members (who volunteer their time and donate and do the slog of grassroots democracy) should see their views better represented by their party, also holds up.

It’s unfair to suggest, though, as Abbott did, that opposition to the motion is solely about the party establishment maintaining its grip on power, and the “insider’s club” protecting its turf.

As Malcolm Turnbull pointed out to the same meeting, the Liberal Party’s membership is in decline, one-sixth of the size it was when he joined. It is not alone in this: party membership has collapsed and Australia has low levels of party membership. Party members now are only the rusted-ons and the true believers. With fewer and fewer Australians satisfied with democracy, politics at a grassroots level has become an exercise for the few and the committed. This is consistent with international research indicating the most ideologically consistent voters are also the most politically engaged, so it’s likely party members are more set in their views and values. That being the case: why shouldn’t someone who volunteers on polling day decide who they are handing out or scrutineering for?

This all follows up to a point, but our MPs aren’t elected to represent their parties; they are elected to represent a particular seat or their state or territory. Party members are more ideological than the general public, and want to preselect someone who shares their beliefs. Fine, but voters are the ultimate decision-makers, and don’t tend to reward extremism. Systems for internal party consistency with a membership base that is rigidly aligned one way or another leaves parliamentary parties open to capture by their extremities, and thus with policies that are unappealing to the majority of voters and no way to reality-test those policies internally.

The Liberal Party inadvertently put this to a real-world trial in the equal marriage survey: there’s no doubt many of them genuinely believed there existed a silent majority of people with conservative views who were against the change but not saying so to pollsters. Some MPs didn’t, and themselves had professed small-l liberal beliefs about marriage before, and it turns out they were right.

Turnbull upheld the deal to debase his climate change and equal marriage views throughout the postal survey and surveyed us all. More centrist MPs could have hoped for a recalibration within the party on some of these issues after the result, a return to a spectrum (dare we say a rainbow) of views held within the party. Instead, there are calls to further match the party to its ever-smaller membership base, as new right-wing parties claim to be capturing disaffected members. So how meaningful can Howard’s “broad church” be if the membership is shrinking, shifting right, and wants to select more MPs? That Warringah returned a Yes vote in the postal survey should be at the top of party decision-makers’ minds, not the views of the member for Warringah.

It’s worth noting this is hardly a problem just for the Liberal Party, as the extended bloodletting over the NSW Greens continues. Labor discontent over factional deals in Victoria continues to boil over as Crikey has reported, and the NSW trials of community preselection seem only slightly more likely to correct back to a sensible, vote-winning centre, leaving open the question of retaining passionate volunteers in a membership base.