Imagine the federal government decided one day that a doctor-prescribed medication you're using is now illegal.

Imagine the government then sent you a notice demanding that you write a letter to them, declaring you have destroyed all your illegal medication. And if you don't, the government says they will pass your confidential medical information -- and that of everyone else using this drug who doesn't write a letter -- to the police.

Improbable as it seems, this is exactly what's happening to more than 37,000 Canadians right now. And apparently the Harper government considers this acceptable, because the medication in question is marijuana.

Health Canada's overhauled medical marijuana program launches this spring. It's been fairly controversial given that it removes the ability of medical pot patients to grow their own, or to buy from a recognized small grower, and hands the entire medical pot industry over to a handful of licensed commercial manufacturers, of which there are so far only 10 for the entire country.

Many medical marijuana users have complained that this corporatization of weed will mean higher prices, potentially threatening their ability to use the drug as prescribed.

But in the most controversial move yet, last week Health Canada issued a notice ordering the 37,000 people with marijuana prescriptions to destroy the pot they grew or bought under the old program, and to send a letter to them declaring they have done so.

"If participants do not comply with the requirement to notify Health Canada, the Department will notify law enforcement," Health Canada stated in a tone nothing short of threatening.

That's right. They're threatening people with police investigation because of the prescription given by their doctor.

There are serious legal and ethical questions here. Is it appropriate for a government to hand over the private medical data of potentially thousands of Canadians to law enforcement, based on that person's medical prescription?

And would the police be justified in raiding the homes of people based solely on the fact they failed to send a letter to Health Canada? I asked the Mounties, and they're being a little vague on the issue.

"The RCMP respects individuals' privacy and will only pursue leads based on information received about potential criminal activity," a spokesperson said in an emailed statement.

But "any marijuana activities not explicitly regulated under the [new medical marijuana rules] as of April 1st, 2014 may be a contravention under the Controlled Drugs and Substances Act," the statement added.

But what it looks like, based on this decree from Health Canada, is that the Harper government is trying to turn the medical marijuana program into a honey pot for law enforcement.

It's turning its list of licenced medical marijuana users, a list of patients in the health-care system, into a list of possible "criminal suspects" -- made criminal overnight by government decree. (Whether or not law enforcement wants this honey pot is another question).

Why am I reminded of the behaviour of totalitarian regimes, which demand public declarations of fealty at the point of a gun? Marijuana policy, meet North Korea.

Even Health Canada's statement is creepy and chilling in its tone. Witness the opening sentence:

Health Canada does not endorse the use of marijuana and is taking the necessary steps to protect public safety while providing reasonable access to marijuana for medical purposes, as ordered by the Courts.

Mentioning that Health Canada "does not endorse" the use of pot as the first sentence of a statement on medical marijuana policy is bizarre to say the least -- it's the bureaucratic equivalent of a temper tantrum.

And you can almost taste the contempt for "the Courts," those bastions of namby-pamby liberals who forced the government to provide marijuana to people legally.

Marijuana activists aren't taking Health Canada's move lying down. West coast pot legalization group Sensible BC is planning a day of action on April 1, the day the Harper government's new rules come into force, to protest all the new rules, including the demand for a letter.

Health Canada "shows why they cannot be trusted to act in the best interest of Canadians who need cannabis-based medicines," the group said in a blog post.

Nor can they be trusted to keep patients' records confidential, apparently; and nor can they be trusted not to be used as a blunt instrument in the Harper government's futile war on marijuana.