Lenient treatment of drug-abusing celebrities is sending a damaging message to impressionable young people, the United Nations drug control agency has warned.
The International Narcotics Control Board (INCB) said a soft approach by police and the courts to well-known names was undermining efforts to reduce drug abuse and eroding confidence in the criminal justice system.
Hamid Ghodse, an INCB board member, said it was regrettable that a "number of people have got a lenient response in the UK and around the world", although he declined to name the celebrities he had in mind.
Last month the singer Amy Winehouse was questioned by police but not arrested over a video that appeared to show her smoking crack cocaine.
The Babyshambles frontman Pete Doherty, meanwhile, was given a suspended jail sentence and a 12-month drug rehabilitation order last year after pleading guilty to possession of crack cocaine, heroin, ketamine and cannabis.
The model Kate Moss has been interviewed by police over photographs of her allegedly taking cocaine, but no charges were brought against her. Chelsea FC sacked their Romanian striker, Adrian Mutu, after he tested positive for cocaine in 2004. The police never became involved.
Professor Ghodse said: "There should not be any difference between a celebrity who is breaking the law and non-celebrities. Not only does it give the wrong messages to young people, who are often quite impressionable, but the wider public become cynical about the responses to drug offenders."
In its annual report published today, the INCB said interest was greater than ever in famous people from the worlds of entertainment, the arts and sport.
It said: "Celebrity drug offenders can profoundly influence public attitudes, values and behaviour towards drug abuse, particularly among young people who have not yet taken a firm and fully informed position on drug issues.
"Cases involving celebrity drug offenders can also profoundly affect public perceptions about the fairness and proportionality of the response of the justice system, especially if there is a less lenient response to similar or lesser offences committed by non-celebrities."
The INCB said Britain had the worst problem with heroin and crack cocaine, while only Spain had a higher rate of cocaine use. It noted that cannabis use was dropping in Britain, although Professor Ghodse registered his concern about the increasing popularity of stronger "skunk" strains of the class-C drug.
Drug taking in Britain
* Heroin use the highest in western Europe.
* Fourth highest use of methadone (heroin substitute) in the world.
* Abuse of crack cocaine "continues to be marginal in all countries in Western Europe, with the possible exception of the UK".
* Second highest level of cocaine abuse in western Europe after Spain.
* Cannabis use dropping, but concern over growing consumption of "skunk".