They seem to be on the increase, with cases of horrifying group rapes in both India and the American town of Steubenville in recent years. But very little had been known about the characteristics, causes and consequences of such crimes which most often go unreported.
Middlesex University's reader in forensic psychology, Dr Miranda Horvath, found a paucity of academic research on the issue of rape when more than one perpetrator carried out the assault.
Using police data, Horvath, working alongside Professor Liz Kelly (London Metropolitan University), realised there were a wide variety of groups of perpetrators carrying out what was often referred to as 'gang rape'. As a result they coined the term multiple perpetrator rape which has now been adopted by police forces and criminal justice agencies across the UK and is widely used in the academic literature.
Dr Horvath explains: "Research on rape and sexual violence had focussed on rapes committed by lone perpetrators. But there was increasing evidence of a small but significant minority of rapes involving more than one attacker. Unfortunately because of the way crime is recorded we cannot say for certain what proportion of rapes are perpetrated by more than one offender."
Concerned by this lack of data and research, Dr Horvath teamed up with Jessica Woodhams (Birmingham University) to launch a British Psychological Society-funded project, Multiple Perpetrator Rape: Setting the Research Agenda Seminar. Together they organised three seminars, bringing together researchers and practitioners – including police officers, policy makers, youth justice workers) – for the first time to work together on the issue of multiple perpetrator rape.
As a result of the seminars Dr Horvath and Dr Woodhams co-edited the first ever Handbook on the Study of Multiple Perpetrator Rape, published by Routledge in March 2013. The Handbook has become a key text for students and academics studying multiple perpetrator rape and an essential reference tool for professionals including police officers, educationalists, forensic psychologists, youth workers, probation staff, lawyers, judges and policy makers.
Dr Horvath has also fostered a collaborative relationship between Middlesex and the Metropolitan police – and sits on its SCD2 (Sapphire – Rape and Serious Sexual Offences Investigation Command) steering group.
"We see this as just the start of the research on multiple perpetrator rape. We want to push ahead, hold more seminars and understand what makes people commit these horrendous offences," says Dr Horvath. "Because our evidence base on this crime is very limited, we don't know whether multiple perpetrator rape is getting more or less prevalent. And we should."