Gay couples could have to prove to a court they are in a sexual and committed relationship under changes to the Bracks Government's same-sex legislation.

And they would have to live together to have the same rights as heterosexual de facto couples. 

The Government was forced to make changes to its controversial Statute Law Amendment (Relationships) Bill after the Opposition said it would destroy long-term relationships such as marriage and the family. 

Independent MPs Russell Savage and Craig Ingram said they would not support the new laws, while Susan Davies had major concerns. 

The Bill is designed to prevent discrimination against same-sex couples and give them similar rights to heterosexual de factos in areas such as property and superannuation. 

It changes the definition of spouse to "domestic partner" in 44 Acts of Parliament. 

Government spokeswoman Jane Wilson said that while most of the 44 Acts referred to domestic partners living together, there may be exceptional circumstances where cohabitation was not possible, such as where one person was in hospital with AIDS or one was a victim of domestic violence. 

The Opposition and independents were concerned that "domestic partner" was defined too broadly. 

"Marriage and de facto relationships require cohabitation and permanency," Shadow Attorney-General Robert Dean said. 

"The Government created this new definition and left out cohabitation and permanency. 

"They have now scrapped the broad definition of domestic partner and included the word couple, which means cohabitation. 

"They are also including a clause which sets out the criteria a judge must consider, which includes permanency." 

Dr Dean said the Opposition would wait to see the amendments, which were expected to go to Cabinet next Monday, before deciding whether to support the Bill. 

Attorney-General Rob Hulls yesterday said the "general philosophy" of the Bill would not change. 

"There might be some additional words added in relation to what a court will have to take into account when defining a domestic relationship," Mr Hulls said. 

Ms Davies insisted on the change requiring a court to consider a list of criteria before deciding if a domestic partnership existed: "There will be a list of criteria that a judge will take into account, such as whether a sexual relationship exists, the degree of mutual commitment to a shared life and the duration of the relationship." 

Her other criteria includes the care of children, the extent of common residence, the ownership of property and degree of financial dependence.