Laura, a law graduate from Dublin, began making a living as a sex worker in the 1990s, spending much of her time in both Edinburgh and Glasgow.
She came to prominence in 2013 after the DUP peer Lord Morrow proposed new legislation which he believed would challenge human trafficking and exploitation.
The most controversial aspect of his bill, now law, was the criminalisation of paying for sex.
The concept, which originated in Sweden, aimed to take legal scrutiny off vulnerable women and put it unto sex buyers, thereby undermining demand from men seen to be exploiting them.
However Ms Lee argued passionately that the measure put independent consenting sex workers like her in danger by making potential clients much more secretive and difficult to screen.
She had been granted leave for a judicial review of the law, which was due to come before the courts.
Her lawyer Ciaran Moynagh said her legal challenge would continue. “We are deeply saddened by the death of our client Laura Lee,” he told the Belfast Telegraph. “Laura courageously fronted a campaign and judicial review which sought to defend and protect thousands of sex workers who do not have a voice. “In the face of much opposition she maintained great dignity. “Laura Lee will be remembered as one of this country’s most fearless human rights advocates and we are committed to continuing her work.”
Laura’s daughter said on Twitter: “I ask you to continue all of your amazing work in her honour. I’m so proud of all my mum accomplished in her tragically short life.”
No further details of her death have been made public.
Ms Lee’s daughter confirmed she died on Wednesday.