MPs hate having to vote on moral issues because they know opponents of change are more likely to change their vote on a single issue than supporters are. Whatever the members might think on the issue, keeping their job is deemed more important. Which is something that perhaps is becoming more understood.
Openly gay Liberal senator Dean Smith questions precedent same-sex marriage public vote sets - ABC News (Australian Broadcasting Corporation):
"The Liberal Party's first openly gay federal parliamentarian has questioned the precedent a plebiscite on same-sex marriage could set. Senator Dean Smith, a vocal same-sex marriage supporter, said a public vote on legalising marriage for same-sex couples may open the door to votes on issues such as military deployment or euthanasia. Writing today for Fairfax Media, Senator Smith said such issues were informed by people's moral views and had just as much impact upon people's personal lives as same-sex marriage."
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