The judge presiding over California’s trial on the legality of a gay marriage ban is expected to hear closing arguments this week.

The trial, which was brought by two Californian gay couples, began in January and continued for three weeks before adjourning.

Judge Vaughn Walker has scheduled a full day of arguments on Wednesday, which will be the final step before he makes a verdict.

His is the first federal court to examine whether the state’s 2008 ban on gay marriage violates the US constitution.

Around 18,000 gay couples married in the state in the few months in which gay marriage was legal. A voter referendum, Proposition 8, struck it down in November 2008.

The two couples – one male and one female – are being represented by Ted Olson and David Boies, who acted on opposing teams in the Bush v Gore case of 2000.

Judge Walker, who was recently outed as gay, has asked the pair and opposition attorneys to address a number of issues in their closing statements.

These include whether the right to marry is a fundamental right, whether it should be, whether gay marriage would harm heterosexual marriage and whether granting gay couples the right to marry would reduce discrimination against them.

Mr Olson told a press conference this week: “Our clients want to have those rights and wish to be treated equally. That is what this case is all about.

“We’re very, very gratified for the opportunity to represent these lovely human beings and hopefully to make a change in this country so that gay and lesbian individuals are treated with the respect that other citizens take for granted.”

During case testimony, the court heard experts testify that allowing gay marriage would help the mental health of gays and lesbians, give more legal protection to their children, reduce discrimination and give gay couples more political power.

Prop 8 supporters put forward only two witnesses, one of who argued that gays are 12 times more likely to molest children.

But their other witness, from a conservative think tank, conceded under cross-examination that children of gay parents would benefit if their parents were allowed to marry.

Judge Walker is expected to rule in the coming weeks, although both sides have said they will contest the case all the way to the US Supreme Court.