A record seven million people — one in every 32 American adults — were in jail, on probation or on parole by the end of last year, according to figures released by the US Justice Department yesterday.

US prisons held 2.2 million inmates, an increase of 2.6 per cent over the previous year. More than 4.9 million adult men and women were on parole or probation, an increase of 27,000 over the previous year.

Prison releases are increasing, according to the report, but admissions are increasing at a greater rate.

The dominant factor, according to experts, is the extremely tough sentencing laws for drug offenders, particularly for low- level possession offences that would be unlikely to attract prison sentences in most European countries. From 1995 to 2003, inmates in federal prison for drug offences accounted for 49 per cent of the population growth in US prisons.

“Over the past 25 to 30 years — since the inception of the ‘war on drugs’ — new laws have insisted on mandatory prison sentences, particularly for drug use,” Cara Gotsch, of the Sentencing Project, a Washington-based reform group, told The Times. “It is quite staggering that some of the harshest sentences are for non- violent drug use.”

She also cited California’s “three strikes” law. It stipulates that if an offender’s first two crimes were serious felonies, then the third crime — no matter how trivial — is subject to a mandatory 25 years to life. In one case, the suspect stole four chocolate-chip cookies.

“That kind of inflexibility in sentencing is a big factor,” Ms Gotsch said. “Judges have less and less discretion on how to sentence, and mitigating factors are not allowed to be considered.”

Racial disparities among prisoners persist. In the 25 to 29 age group, 8.1 per cent of black men — about one in 13 — are incarcerated. The figure for Hispanic men is 2.6 per cent and just 1.1 per cent for white men. By the end of 2005, black women were more than twice as likely as Hispanics and more than three times as likely as white women to be in prison.

More than nine million people are held in penal institutions across the world. The US has the highest number of prisoners. Russia holds 860,000, while China says officially that it holds 1.51 million, but that figure does not include prisoners in “administrative detention”.

In England and Wales, a total of 288,500 are in jail, or on probation or parole. That is one in every 135 adults. Men still far outnumber women in prisons and jails, but the female population is growing more quickly.

Over the past year, the female population in state or federal prison in the US increased by 2.6 per cent, while the number of male inmates rose by 1.9 per cent. By the end of the year 7 per cent of all inmates were women.

Locked up

• 2.2m prisoners in US jails
  
• 4.9m people on parole
  
• 8.1% of black men aged 25 to 29 in prison
  
• 1.1% of white men aged 25 to 29 in prison
  
• 7% of inmates female

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