It's speaking as the Australian government's been urging people to provide them with their opinions on the introduction of same-sex marriage as part of their consultation. It was receiving responses up until Friday.
The Australian coalition government wanted to hold a referendum where the people could decide whether same-sex marriage should be brought in, however this proposal was blocked by the Australian Senate.
Some senators argued a referendum would prompt hateful language and behaviour, however others, including the ACL, believe all Australian people should have a say on the issue rather than just elected politicians.
A draft bill legalising same-sex marriage currently does not require ministers and churches to perform them if they don't want to, and also provides exemptions for some businesses to refuse services if they feel the requests would go against their viewpoints on sex and marriage.
LGBT campaigners have been arguing for those exemptions to be dropped, saying they could encourage discrimination.
The ACL has welcomed the exemptions, citing the case of Asher's Bakery in Northern Ireland where a Christian business was taken to court for refusing to make a cake with a slogan supporting gay marriage.
The lobby group has also called for the exemptions to be expanded to ensure cases like that of Ashers do not happen in Australia.
According to The Guardian the ACL told the Senate's consultation that same-sex relationships should not be given marriage status because children are not a central part of them in the way they are in a couple composed of opposed sexes.
It said: "Where gender is erased from the fundamental group unit of society, it logically follows that gender becomes increasingly confused at all levels in the community.
"If marriage is a child-centred institution it reasonably follows that [it] is not a category of relationship that can reasonably apply to same-sex relationships, which do not bear even the possibility of producing children."
