By Peter Reynolds

Over 203,000 people have signed the petition on the government’s website to "make the production, sale and use of cannabis legal". All petitions that pass 100,000 signatures are considered for a debate in the House of Commons and when MPs return from their summer break, the petitions committee will have a hard time refusing a debate on a petition that has double the required threshold.

Yesterday the government published its response to the petition. It consists of the same misleading words the Home Office has been parroting for many years. They are also the same words which dozens of MPs have used to dismiss their constituents' letters and emails on the subject. You can read the response in full here (and sign the petition, if you haven't already done so).

It is Home Office policy to mislead the public about cannabis. The government’s response starts:

"Substantial scientific evidence shows cannabis is a harmful drug that can damage human health. There are no plans to legalise cannabis as it would not address the harm to individuals and communities."

This claim could be applied equally to almost any substance, ranging from digestive biscuits to crack cocaine. It is difficult to argue with a statement that is devoid of any substantive meaning. It is only intended to deflect and mislead. It cannot stand up to any scrutiny. To have any meaning, the potential harms of cannabis have to be compared with potential harms from other substances.

Recent research from Universities in Germany and Canada show that cannabis is 114 times safer than alcohol.

Just three weeks ago the University of Pittsburgh published a study that tracked over 400 men from early adolescence to their mid-thirties. It showed that there was no difference at all in physical and mental health outcomes between different control groups ranging from those who used no cannabis, to those who were regular, heavy users.

The myth, popular amongst tabloid columnists and misinformed MPs, that cannabis causes severe mental health problems in young people has also been comprehensively debunked. The truth, as revealed in a recent parliamentary answer, is an average of just 28 cases per year of cannabis psychosis. Of course, these are individual tragedies but this cannot be the basis on which to allocate £500 million per year of law enforcement resources and criminalise three million regular users.

It is also undoubtedly true that properly regulated, labelled and controlled cannabis would be far safer than the 'moonshine weed' grown by criminal gangs. A regulated market would impose age limits, eliminate dangerous hidden cannabis farms and get dealers and violence off our streets.

There is also increasingly strong evidence of the very beneficial effects of cannabis as a safe, non-toxic treatment for chronic pain, multiple sclerosis and cancer - particularly the debilitating effects of chemotherapy.

There have been dramatic results from human trials in treating Crohn's disease, with 95% of participants experiencing significant improvement in symptoms.

Perhaps most exciting of all is strong evidence, now repeated in several studies, that moderate regular use of cannabis in middle age can delay and even prevent the onset of Alzheimer's. It has emerged that the US government now holds a patent on cannabis for its neuroprotective qualities and for use as a treatment for stroke, brain injury and Parkinson's.

The government response also rejects the idea that substantial tax revenue could be raised by taking the £6 billion per annum cannabis market out of the black economy:

"…there would be costs in relation to administrative, compliance and law enforcement activities, as well as the wider costs of drug prevention and health services".

It is unfortunate that the petition used data from the Institute of Social and Economic Research, which found legalising cannabis could bring in £900 million in taxes every year, save £400 million on policing cannabis and create over 10,000 new jobs. The study was fundamentally flawed in that it failed to project revenue based on a cannabis tax as implemented in jurisdictions such as Colorado and Washington, where legalisation is proving a roaring success.

My organisation, Clear, commissioned independent research in 2011 which showed a net gain to the UK economy, after costs, of between £6.7 billion to £9.5 billion per year on current levels of consumption.

The government's response to the petition is weak, and out of touch with public opinion, evidence and the reforms which are taking place across the world. It demonstrates a determination to continue deceiving the country, based on a dishonest assessment of the vast amount of evidence that is available.

While ministers are happy to admit use of cannabis in their past with a chuckle and a wink, they endorse and support a policy which brings severe consequences down on the heads of ordinary people. It also diverts police attention and resources from the serious crime which causes real harm, all in the name of persecuting people who want to use or grow cannabis in the privacy of their own home.

Peter Reynolds is president of Clear Cannabis Law Reform. Clear has prepared guidance on how to lobby MPs to ensure that a debate takes place and that the evidence is properly considered

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