Early research by the Home Office has shown there is a strong link between hard drug use and crimes such as robbery.

Anti-drugs coordination minister Bob Ainsworth disclosed that addicts who tested positively for three or more types of illegal drug had carried out on average three times the number of criminal offences as people arrested for offences who were drug-free.

His written answers to Labour backbencher Paul Stinchcombe revealed that more than 40 per cent of people arrested thought their drug use and crime were connected.

When asked about this connection, more than two-thirds said that this was due to the need for money to buy drugs.

On average users reported generating just over £5,000 to pay for their habits mostly through property crime.

Researchers estimated that on average a heroin or cocaine addict commits 200 crimes-a-year against 52 crimes committed by those who do not use those drugs.

Hard drug users are subject to twice as many arrests a year as offenders not taking drugs.

Ainsworth warned that research was in the early stages.

"Recorded crime figures include statistics on drugs offences and on acquisitive crimes, such as burglary, but do not record whether the latter are related to an offender's drug habits," he said.

"Levels of drug-related crime cannot be measured directly as no routine statistical data are collected on whether an offence may have been committed as a result of drug taking. The research is insufficiently advanced to reveal the precise links between drugs and violent crime."