A leaked pamphlet in the battle for marriage equality in Australia has claimed that children will be subject to “abuse and neglect”, if they’re raised by same-sex couples.

Authorised by former parliamentary secretary to ex-Prime Minister, John Howard, the document indicates where potential battle lines could be drawn for a ‘no’ vote in the upcoming national vote on the issue.

As well as claiming that children from same-sex families are more prone to “abuse and neglect”, it also says they are likely to become unemployed, abuse drugs and suffer from depression.

The pamphlets, which were obtained by Fairfax Media, were funded by former Liberal MP Chris Miles.

He served in Canberra between 1984 and 1998 and co-founded a group of conservative MPs.

The documents claims that “married biological parents have a better record for providing safety and development of healthy, well adjusted adult children.”

It adds that in these households their chance of abuse and neglect is reduced.

The pamphlet claims the information is based on a report to the US Congress by the Department of Health and Human Services.

A number of accusations are made, such as children with same-sex parents will be more likely to suffer from “suicidal thoughts”, compared to their peers in mixed-sex families.

Mr Miles said that if a plebiscite was going to happen “people needed to be informed”.

“Lots of things are hurtful to people in Australia. Everyone hurts on a whole range of views,” added Mr Miles.

“These will be distributed throughout Australia at the grass roots.”

When asked if he thought the pamphlet was hurtful, he said it was “thoughtful and constructive”.

Marriage equality campaigners and parliament’s main opposition party, Labor, have said that the vote is unnecessary and will only lead to unwarranted attacks on the LGBT community.

Rodney Croome, director of Australian Marriage Equality, said this was just the start of anti-gay information that will continue if the government insist on holding a vote.

“Not only is the information on this flyer wrong, it will put the lives of young gay people and the children of same-sex couples at risk by reinforcing the message that they and their families are broken,” he said.

Dr Liz Short, who conducted a review into same-sex parenting for the Australian Psychological Society, said the pamphlet was “factually incorrect and deeply damaging”.

Opposition leader, Bill Shorten added that it demonstrated “unhinged abuse” and reemphasised his calls for a free vote in parliament to settle the issue.