Just for talking common sense in Canada, a federal cabinet minister can come under vicious attack.

Justice Minister Anne McLellan came under a barrage of hostile flack when she said scientific studies were needed to determine whether medicinal marijuana was effective and safe before government became a purveyor of marijuana and permitted doctors to prescribe it.

McLellan simply wanted proof that marijuana would do more good than ill. This standard is applied to all prescription drugs. It takes years of careful testing before any drug comes to market.

If the government even considered opening the door to a prescription drug that had been subject to as little medical testing as marijuana, howls of justified outrage would be heard across the nation. Less legitimately, the media would be full of stories of a U.S. plot to aid its multi-national pharmaceutical companies by pushing unsafe drugs.

Yet, when McLellan called for adequate testing of medical marijuana claims, the media was full of stories of a US plot, designed to deprive sick Canadians of the miracle drug marijuana for the sake of the US war on drugs.

There are many good reasons to legalize drugs like marijuana and even harder drugs. Our laws create incentives for pushers to hook kids on drugs. They leave the trade unregulated and underground. They encourage a secondary wave of crime as addicts seek the means to feed their addictions. They create a huge subsidy program for organized crime, as did prohibition in the 1920s.

But, this gives no license for quack fantasies in support of medicinal marijuana. Government should never risk misleading truly sick people about the effects of any medicine when those effects have not been fully studied.

The call for medicinal marijuana is based on some truly appealing anecdotal evidence. Over the last couple weeks, Canadians saw people suffering from tragic conditions explain to the television camera how marijuana improved their lives.

Quack medicine like the many miracle cancer cures is based on such anecdotal evidence. Thousands of people have been fooled and had their suffering exacerbated by cures supported by anecdotal claims. Scientific study is needed to assess the claims.

What is the state of the scientific literature on medical marijuana? A recent editorial in the British Medical Journal (BMJ) argued that the current information is that the adverse effects of cannabinoids outweigh their effectiveness.

Two central claims are made for medical marijuana that it can reduce pain and nausea. The BMJ editorial was based on reviews of the current literature on marijuana’s effectiveness in both areas.

The review showed that marijuana was no more effective than codeine in pain relief. Marijuana had some effectiveness in controlling moderate nausea, but not severe nausea. The studies found a number of negative side effects. Most of the studies reviewed were dated. Since then, a number of newer more effective pain and nausea medications have come on the market.

McLellan is dead-on when she worries that medicinal marijuana could, like quack medicines, encourage people to drop effective treatments for a less effective treatment with dangerous side effects.

At the same time, rapid progress is being made in isolating the chemicals in marijuana, which provide benefits and separating them from those which can cause harm. Ajulemic acid is a synthetic derivative of delta-9-tetrahydrocannabinol (THC), the marijuana compound that reduces pain and creates a high. Scientific tests suggest that ajulemic acid is up to 50 more effective than THC in reducing pain, and it does not create a high.

Canada’s courts are responsible for a large part of this mess. An Ontario Court of Appeal made it legal for terminally ill people to use marijuana for pain relief. This shows how irresponsible courts can be when they, rather than our elected officials, decide policy. Such decisions should be made based on scientific evidence, not the predilections of judges.

There are many reasons to legalize drugs. Junk science is not one of them. It could victimize thousands of already desperately sick Canadians.