When information on a further 1715 people charged with rioting offences was issued a month later, the focus was on the fact that 73 per cent of the defendants had a previous caution or conviction. Few noted that the ministry had chosen to focus only on male rioters; females were absent from these ''average'' recidivists. What we saw was a palpable concern with the youth, class and race of rioters but a lack of analysis of the key fact the statistics illustrate: the culpability, and cost, of masculinity. As so often, masculine antisocial behaviour was just the wallpaper. In 1959 the social scientist and policy activist Barbara Wootton looked at the crime statistics and remarked that ''if men behaved like women, the courts would be idle and the prisons empty''. Half a century later, the British Crime Survey and police crime figures bear her out. In 2009-10, men were perpetrators in 91 per cent of all violent incidents in England and Wales. Ministry of Justice figures for 2009 show men to be responsible for 98 per cent, 92 per cent and 89 per cent of sexual offences, drug offences and criminal damage respectively. Of child sex offenders, 99 per cent are male. The Ministry of Justice publishes an annual report, Women and the Criminal Justice System, the purpose of which is to fulfil the ''equality'' provision in the 1991 Criminal Justice Act.

But looking at statistics on women conceals the obvious: a comparable report on men and the criminal justice system would be policy dynamite. On the road, men commit 87 per cent of all traffic offences and 81 per cent of speeding offences. More people are killed and injured in road accidents than anywhere else, and Home Office data reveal the bearing of masculinity here too: men are responsible for 97 per cent of dangerous driving offences and 94 per cent of motoring offences causing death or bodily harm. A World Health Organisation report in 2002 on gender and road traffic injuries cautiously broke the code of silence by remarking that masculinity ''may be'' hazardous to health. Some of the costs of masculinity are paid individually. Boys are ''permanently excluded'' from school at a rate four times higher than girls and achieve lower academic scores. But what of the overall costs to society? Take prison costs alone - an estimated £45,000 ($A72,000) a prisoner a year. Ninety-five per cent of those prisoners are male. If men committed crimes leading to jail at the rate women do, the government would save about £3.4 billion a year. Zoom out to the overall cost of crime, calculated by the Home Office at £78 billion a year in 2009, including not only criminal justice system costs but lost productivity, service costs, and impact on victims.

If men committed as few crimes as women, the overall number of incidents would fall by 54 per cent. This creates an annual saving of £42 billion, which would wipe out the public sector budget deficit three times over. However, the most masculine crimes are the most expensive. A homicide, a sexual offence and a serious wounding cost £1.4 million, £31,438, and £21,422 respectively (2003 figures). The most feminine crime, theft, is the cheapest, at £844 an incident. Thus the real saving to the UK of such a change in male behaviour would be vastly greater. How men and women behave is socially shaped. Popular understandings of masculine characteristics play up biology. Testosterone, the male hormone, the ''metaphor of manhood'', is portrayed as driving men inexorably towards aggressive behaviour. Yet studies show that testosterone is related to status-seeking but not directly to aggression. Many other factors are influential. Testosterone levels are increased or diminished in both males and females by diet, activity and circumstance.

The opportunity to interact with guns, for instance, appears to increase testosterone, while men's testosterone levels fall when they are involved with the care of children. The case we are making is that certain widespread masculine traits and behaviour are dangerous and costly to individuals and society. They are amenable to change. The culture of masculinity can be, and should be, tackled as a policy issue. GUARDIAN Cynthia Cockburn is honorary professor in the Centre for the Study of Women and Gender, Warwick University. Ann Oakley is professor of sociology and social policy at the University of London.