Reliable evidence of the frequency and severity of human rights abuses in Haiti after the departure of the elected president in 2004 was scarce. We assessed data from a random survey of households in the greater Port-au-Prince area. Methods Using random Global Positioning System (GPS) coordinate sampling, 1260 households (5720 individuals) were sampled. They were interviewed with a structured questionnaire by trained interviewers about their experiences after the departure of President Jean-Bertrand Aristide. The response rate was 90·7%. Information on demographic characteristics, crime, and human rights violations was obtained. Findings Our findings suggested that 8000 individuals were murdered in the greater Port-au-Prince area during the 22-month period assessed. Almost half of the identified perpetrators were government forces or outside political actors. Sexual assault of women and girls was common, with findings suggesting that 35 000 women were victimised in the area; more than half of all female victims were younger than 18 years. Criminals were the most identified perpetrators, but officers from the Haitian National Police accounted for 13·8% and armed anti-Lavalas groups accounted for 10·6% of identified perpetrators of sexual assault. Kidnappings and extrajudicial detentions, physical assaults, death threats, physical threats, and threats of sexual violence were also common. Interpretation Our results indicate that crime and systematic abuse of human rights were common in Port-au-Prince. Although criminals were the most identified perpetrators of violations, political actors and UN soldiers were also frequently identified. These findings suggest the need for a systematic response from the newly elected Haitian government, the UN, and social service organisations to address the legal, medical, psychological, and economic consequences of widespread human rights abuses and crime