With three separate polls released over the past couple of months gauging public opinion on same-s-x marriage, it’s worth taking a squiz at how opinion has changed over the past few years, as well as breaking the results down to look at how there is a fairly wide variation on views among demographic cohorts.

First up, this is what the polling looks like going back to 2004 — the lines are the historical time series, the column charts are the polls from this year.


Over the longer term, we’ve see support for same-s-x marriage increase throughout the community — however, over the past two months, something interesting may have happened.

When it comes to issue polling in Australia, there’s a substantial proportion of the population whose mental autonomy on any given issue is fairly questionable, where they believe (or at least, say they believe) whatever their position is of the party they vote for.  If a party changes its policy from supporting some particular issue to opposing it, so too does a significant chunk of the population. We witnessed that with the CPRS debate, where we saw a decent level of support for it from Liberal Party voters under Turnbull, but then  a few weeks later under Tony Abbott’s leadership, that support collapsed.

What we’ve seen over the past few months is the issue of same-s-x marriage getting a much higher profile in the media and politics than usual — so I wonder if what looks to be the recent, short-term decline in support is simply a function of several politicians being loud in their public  opposition to the idea of same-s-x marriage?

We can slice and dice these polls in several ways to see what is happening underneath the top-line numbers. First, we can pool all three polls to look at support by party vote:


We have a somewhat expected result of the ALP vote being moderately for the issue, the Coalition vote being weakly against the issue and the Greens vote being very strong on the issue.