Gina Martin
Activist Gina Martin poses for a portrait in London. After two years of fighting to criminalize "upskirting," or the practice of taking a photo under someone's skirt or kilt without consent, Queen Elizabeth II gave an upskirting bill a Royal Assent, making it illegal in the UK. ADRIAN DENNIS/AFP/Getty Images

The practice of "upskirting," or taking photos under a skirt or kilt without the wearer's consent, became a criminal offense Tuesday after Queen Elizabeth II officially signed a bill into law.

The bill received a Royal Assent, which under British law finalizes a bill, after it was approved in January by the House of Lords. The law goes into effect in April.

Activist Gina Martin spearheaded the criminalization of upskirting after she became a victim in 2017. As the BBC reported, the incident occurred when a man took a photo of Martin's crotch while she attended an outdoor music festival.

Martin reported the incident to authorities, only to learn that upskirting was not illegal. She then took to social media to speak about her experience, which went viral.

Martin would later launch a long campaign for the criminalization of upskirting.

When asked by the Press Association as to whether she felt her work was finally done, Martin replied that her work was "far from over."

"There's a huge job to do in creating narratives around this thing, we still see 'smaller' sexual assaults as not such a problem but it's a massive issue," said Martin.

"It has been a long time coming but we are finally protected in every scenario - as we should always have been," she added.

Prime Minister Theresa May backed the legislation, emphasizing her approval of seeing "degrading practice of upskirting become a criminal offense after the tireless work of victims and campaigners."

U.S. lawmakers are also looking to criminalize upskirting, though laws vary by state.

Brandon Lee Gary, a Georgia grocery store employee, was convicted on a felony charge of unlawful eavesdropping after taking an upskirting video in 2013. However, his conviction was later overturned because he did not violate the state's invasion of privacy law.

"It is regrettable that no law currently exists which criminalizes Gary’s reprehensible conduct," Judge Elizabeth Branch stated in her ruling.

A Massachusetts man's 2014 conviction was also overturned because of technicalities in the law.