Calls for downblousing to be made a criminal offence in England and Wales
Law chiefs want the act of taking photos down a woman's top without consent, or "downblousing", to be made illegal in England and Wales.
New proposals also aim to protect victims of intimate image abuse and revenge porn by changing current laws.
The Law Commission, which reviews and updates legislation, is also calling for a ban on sharing pornographic deepfakes without consent.
The government said it would carefully consider the recommendations.
Current state of play
At the moment in England and Wales, acts such as upskirting or voyeurism are criminalised, but the recommendations would extend this further.
Northern Irish Justice Minister Naomi Long, who strengthened the law in this area in Northern Ireland, told the BBC: "New offences have been created for upskirting, downblousing and cyber-flashing where those convicted will be liable to a maximum of two years' imprisonment.
"I believe these new provisions will offer greater protection in Northern Ireland and that it will have a real, tangible and positive effect for victims," she said.
In Scotland, upskirting has been banned since 2010, with the Sexual Offences (Scotland) Act 2009, which outlaws sexual crimes, amended to include upskirting in a widened definition of voyeurism.
Prosecutions of the crime in Scotland have remained low since it was brought into scope, with an average of three upskirting prosecutions a year between 2011 and 2018.
Protecting victims
Numerous victims of intimate image abuse have described how distressing the experience has been.
Emily Hunt, who was filmed naked in a hotel room while she was unconscious in 2015, spent five years campaigning for her perpetrator to be brought to justice.
"It completely derailed my life," she said.
Prosecutors told Ms Hunt that what the man did was not illegal, until the law was clarified by the Court of Appeal.
"They told me it was not against the law to video someone naked if you were in the same room as them. I started campaigning, trying to let politicians know that they need up-to-date laws.
"The current 'patchwork' of criminal offences has not kept pace with how technology is evolving."
Sophisticated technology means there are more pornographic deepfakes out there too; videos manipulated so that the original face is replaced with somebody else's. There is also tech that can let users "nudify" pictures.
Gaps in the law mean perpetrators can evade prosecution for actions that cause severe distress and long-term harm to those targeted. Victims should also receive anonymity for life, the commission said.
Folami Prehaye became a victim of revenge porn when her former partner Thomas Samuel posted explicit pictures of her online.
He shared the images with her friends, family and strangers, and was given a six-month suspended sentence for harassment and distributing indecent images.
Like Emily, Folami has now become a campaigner for change, and founded the group Victims of Image Crime.
"As someone who has first-hand experience, I felt it important for any new suggested changes to take on board the voices of those who have fought for justice," she told the BBC.
"My hope is that the Law Commission has covered 'threats to share', anonymity for all experiencers and the need for them not to prove intent."
The key proposals are:
- It would be an offence for someone to intentionally take or share an intimate image of a person without their consent
- This new base offence would apply regardless of the perpetrator's motivation and could lead to a maximum sentence of six months' imprisonment
- If someone takes or shares an intimate image without consent to obtain sexual gratification, or to cause humiliation, alarm or distress, threatens to share an intimate image, or installs hidden equipment, they could receive a sentence of two to three years' imprisonment
Prof Clare McGlynn, from Durham University, said the Law Commission's proposals are a welcome step - especially making the taking or sharing of an intimate image without consent a base offence.
"The breach of privacy and breach of consent is the core wrong, so it's right to focus on that," she said,
Reforms would make it easier to prosecute for a wider range of behaviours, with tougher sentences handed out for the most serious abuse.
But Prof McGlynn adds that the proposed recommendations are "long overdue".
"We really do need prompt action because the government and politicians could have taken steps years ago and saved thousands of young people from being harmed by intimate image abuse.
"And that's what we need to remember - every day that we're not introducing these new laws, people, especially young women, are being harmed, and some of these harms are life-threatening."
Prof Penney Lewis, the law commissioner for criminal law, said: "Sharing intimate images of a person without their consent can be incredibly distressing and harmful for victims, with the experience often scarring them for life.
"Current laws on taking or sharing sexual or nude images of someone without their consent are inconsistent, based on a narrow set of motivations and do not go far enough to cover disturbing and abusive new behaviours born in the smartphone era."
However, Kate Isaacs, founder of Not Your Porn - which aims to hold the porn industry accountable for the distribution and commercialisation of non-consensual material - said: "The thing that concerns me the most is it doesn't look like there's anything in terms of profiting from [image-based sexual abuse] or platform responsibility here, which is really worrying.
"Addressing the installation of equipment such as a hidden camera is all very well and good, but I've worked on a number of cases with women who have been secretly recorded without their consent and then that footage has been uploaded to a platform that has allowed someone to profit from that content."
A government spokesman said: "Nearly 1,000 abusers have been convicted since we outlawed 'revenge porn'.
"With the Online Safety Bill, we will force internet firms to protect people better from a range of image-based abuse - including deepfakes.
"But we asked the Commission to explore whether the law could be strengthened further to keep the public safer.
"We will carefully consider its recommendations and respond in due course."
Follow Shiona McCallum on Twitter @shionamc