When the trans sex worker Paola Buenrostro was killed by a client in Mexico City, her friend Kenya Cuevas grabbed the man to stop him fleeing and recorded the scene as police arrived amid sirens, screams and red and blue lights. Despite the footage and witness testimonies, a judge considered there was insufficient evidence to hold the man and released him after 48 hours, since which time he has been on the run. That night in 2016 turned Cuevas into an activist. And last week, after years of campaigning, Mexico City passed a law making transfemicide a crime with a prison sentence of up to 70 years – a “watershed” moment in one of Latin America’s deadliest countries for trans people.