A Liberal Senator has proposed a rival same-sex marriage bill that would curtail anti-discrimination laws in order to “preserve” religious freedoms.

The draft legislation, released by Senator James Paterson on Monday, competes with fellow Liberal Senator Dean Smith’s marriage bill.

Senator Paterson’s proposal would allow a person or business to refuse service related to a same-sex wedding. Government employees would be protected for refusing to register a same-sex marriage.

The bill would protect “relevant beliefs” that “the normative state of gender is binary” and “sexual relations should only occur within a marriage”. It gives celebrants and chaplains the power to determine a person’s gender and supersede the legal status of their gender.

The bill would also guarantee the right of parents to opt their children out of school classes that conflicted with their values.

It seeks to protect freedom of speech and enacts a narrow anti-detriment clause, which would prevent governments and agencies taking adverse action against someone with a traditional view of marriage.

Under the proposal, the federal law would quash state and territory anti-discrimination protections.

Unlike Senator Smith’s bill, Senator Paterson’s proposal would not remove the definition of a marriage as between “a man and a woman” and would instead add an additional clause that marriage can be “the union of two people”.

Cabinet minister Mathias Cormann said his personal instinct was that the Smith bill was “probably a good starting position” because it had been subject to a cross-party Senate committee process.

“But I suspect it will need improvement in terms of strengthening religious protections,” he told ABC radio.

Ultimately it was up to Parliament to decide which bill was the “vehicle to facilitate” the parliamentary debate.

“There won’t be a government position, there won’t be a party position,” Senator Cormann said.

Senator Paterson, who voted yes in the marriage postal survey, says any ensuing law changes shouldn’t have negative consequences for opponents of same-sex marriage.

“If the parliament opts for a narrower bill with fewer protections, I fear we will see some Australians seek to impose their values on others, with court cases and other legal mechanisms,” he said in a statement announcing the draft bill.

“I’ve never believed that allowing same-sex couples to marry needs to come at the expense of the freedoms of other Australians.”

Senator Paterson believes state and federal anti-discrimination laws aren’t strong enough.

Almost eight in 10 Australians who received the Australian Bureau of Statistics same-sex marriage survey form have already had their say.

The survey result will be announced on Wednesday.