Drug users are being let off because police do not want to harm their ‘life chances’.

Officers are being told not to charge or hand out warnings to everyone caught with the class B drug.

Dave Thompson, who is chief constable of West Midlands Police, told MPs he did not want to ‘criminalise lots of young people’.

‘We took some policy decisions about what we do about cannabis,’ he said. ‘My answer is let’s not give everyone a cannabis warning – it’s disastrous for their life chances.’

West Midlands Police Chief Constable David Thompson told MPs he did not want to ‘criminalise lots of young people’

The guidance is being given despite the West Midlands being dubbed Britain’s ‘cannabis capital’. More cannabis plants are found there than anywhere else in the country, according to Home Office figures.

The force, which is the country’s second largest, seized 36,316 plants last year with an estimated street value of £36million.

However only 14 offenders were charged and six cautioned. Arrests for possession and production of the drug across the region have fallen by 60 per cent in a decade.

Officers seized £2.5 million-worth of cannabis and a weapon covered in faeces in a raid at Brownhills Business Park in Brownhills, West Midlands

Mr Thompson told the House of Commons home affairs committee last week that his officers often found ‘huge amounts of cannabis’ when carrying out stop and searches for weapons.

But he suggested the offenders should escape punishment for possession: ‘I don’t set out the strategy to criminalise lots of young people.’

A cannabis warning involves asking an offender to sign a paper form explaining the Misuse of Drugs Act.

Just an hour after that raid, another team from the force busted a second monster factory seven miles away in West Bromwich

Jan 2019 - police in Brierley Hill discovered yet another cannabis factory with dozens of plants, which an officer involved in the raid posed in front of

Anyone given such a warning would not have a criminal record, but their details would be recorded on the Police National Computer and might be disclosed to employers in an enhanced check by the Disclosure and Barring Service.

David Raynes of the National Drug Prevention Alliance questioned Mr Thompson’s approach.

‘While chief officers have to prioritise use of their resources, they do not and should not attempt to make the law,’ he said. ‘That is for Parliament, and both main parties have consistently been against drug legalisation/normalisation.

A major cannabis factory spread across three floors of an empty towerblock, Birmingham

‘The chief officer and his police and crime commissioner are acting irresponsibly. The grave danger of the chief constable’s attitude is that his policies will encourage use, dealing and production in the West Midlands.

‘As we have seen with the Netherlands that has long-term effects in terms of other drugs and associated serious crime including violence.’

David Green, of the think-tank Civitas, said: ‘There seems to be a policy of unofficial legalisation of cannabis in the West Midlands despite the fact many doctors are becoming much more concerned about cannabis than ten years ago because of increasing potency and the risk of schizophrenia and mental health problems.

On April 1, police in the Neachells area of Birmingham discovered 100 plants, worth £100,000, growing under lamps in an outbuilding of a house

‘The figures seem to show that the West Midlands is the cannabis capital of the UK and there is no better way to ensure that is the case than a police policy not to prosecute.’

National figures show arrests for possession of cannabis have almost halved from 160,700 in the year to March 2010 to 82,026 last year.

The Police Federation has called for a debate on drug laws as stretched forces try to stem the rise in violent crime. Sergeant Simon Kempton, who speaks for rank-and-file officers on drug matters, said: ‘I agree with Dave Thompson completely.

‘No one is saying cannabis is safe but I do not want to see young people criminalised when their only offence is possession because it does affect their life chances and it seems unlikely to stop them smoking cannabis.

Police said the funds would have otherwise gone to serious organised crime groups. Neachells bust pictured

‘Officers are stretched and the public would want us to put resources into tackling crimes causing the most threat and harm to the public.

‘However, there is value in terms of cannabis seizures as that almost always involves organised crime groups who may use violence and intimidation.’

Police chiefs and elected police commissioners have also spoken of the need to soften legislation concerning cannabis use. Mike Barton, chief constable of Durham, has called for the legalisation of cannabis, saying criminalisation has failed.

One of the West Midlands's largest ever cannabis factories was uncovered by police in August

Only last week the Mail revealed that children as young as nine are being admitted to hospital with severe disorders caused by cannabis.

A West Midlands Police spokesman said officers had been told out-of-court options such as cautions and fines were appropriate for cannabis possession. ‘Rates of cannabis warnings are being tracked,’ added the spokesman.

Elaborating on his remarks to MPs, Mr Thompson said: ‘My comments related to young people with small amounts of cannabis when we were looking for knives, for whom, there may be an alternative to a life-changing arrest and criminal conviction.

A £2.5million operation saw 2,400 plants growing across 19 rooms in two separate industrial units near Birmingham in June

‘Let me be clear, the active pursuit of those who deal in the misery of drugs is a fundamental part of policing in the West Midlands.’

A Home Office spokesman said: ‘There is clear scientific and medical evidence that cannabis is harmful, which is why it is a controlled drug.

Possession of cannabis is a criminal offence and supply an even more serious offence. The police have a range of powers at their disposal to deal with drug-related offences in a way that is proportionate to the circumstances of the offender and the public interest.

How police choose to pursue investigations is an operational decision for chief constables, but we are clear that we expect them to enforce the law.’