Upskirting becomes a specific criminal offence on Friday – punishable by up to two years in prison.

The vast majority of cases involved female victims and male perpetrators, according to data released by police forces under Freedom of Information laws.

The law comes into force following a high-profile campaign led by writer Gina Martin, who spent 18 months fighting for it to be made a specific offence after two men took a picture up her skirt at a festival in 2017.