After some setbacks, the UK's bill forbidding "upskirting" has become law. The Voyeurism Act takes effect in April and gives creeps up to two years in prison if they take photos under a person's clothing without consent for the sake of "sexual gratification or to "cause humiliation, distress or alarm." The most egregious perpetrators will also find themselves on the sex offenders register. Summary convictions can involve a year in prison, a fine or both.
Victims are also entitled to some automatic protections, such as keeping their names out of the press.
Upskirt photos have been prosecuted before as Outraging Public Decency offenses, and they were already specific crimes in Scotland. There were some instances where they weren't necessarily illegal, however. The Voyeurism Act is meant to both cover that gap and send a message to would-be perpetrators. Although there's no guarantee this will deter criminals (that may depend on real-world sentencing), it should ensure they face at least some form of punishment.