For Justin Trudeau, making the legalization of marijuana a key plank in his election platform was relatively easy.

Now his government faces the complicated – and potentially controversial – task of regulating the distribution and sale.

These are not uncharted waters. A handful of American states have recently taken the plunge, and the experiences in Alaska, Colorado, Oregon, Washington and the District of Columbia provide examples of how marijuana sales could be introduced in Canada.

Some states have purchasing minimums, while others only limit how much an individual can possess. Some states have licensed retail dispensaries, but others only allow marijuana to be grown at home. A shop can sell magic brownies in some, but only the bud (or flower) of the cannabis plant in others.

Here’s what legalized marijuana currently looks like in the United States:

Where is marijuana legal? In December 2012, both Washington and Colorado made recreational marijuana legal. On Jan. 1, 2015, Oregon added its name to the list, followed by Alaska and the District of Columbia in February.

Who can use it? Recreational users must be 21 or over in each of these jurisdictions, the same as the drinking age.

Where can you buy it? Washington, Oregon and Colorado have licensed retailers who sell marijuana products. In Alaska and the District of Columbia, consumers are allowed to grow plants for personal use, and give away small amounts, but not sell it for a profit.

What does it cost? Depending on the strain, marijuana sells for anywhere between $8 and $20 a gram.

Is it taxed? In Washington, the normal sales tax applies to purchases, but retailers must pay the government a 37 per cent marijuana excise tax. In Colorado, there is a 25 per cent sales tax. In Oregon, dispensaries will collect a 25 per cent tax on all recreational marijuana products starting in January 2016. Alaska, which has legalized the use of marijuana but is still figuring out how to sell it, lawmakers have discussed levying a $50-per-ounce fee.

How much can you have?

Washington: Up to 28 grams of marijuana, 7 grams of marijuana concentrate/extract for inhalation, 454 grams of marijuana-infused product in solid form, and 2.3 litres of marijuana-infused product in liquid form.

Oregon: Residents can have up to 227 grams of marijuana in the home, and 28 grams of marijuana outside of home, but can only purchase 7 grams a day.

Colorado: Residents can possess up to 28 grams of marijuana, but people who are not Colorado residents can only buy 7 grams at a time.

Alaska: Alaska: Proposed regulations would allow consumers to buy up to 28 grams of marijuana, 454 grams of edibles, seven grams of extract or 2.3 litres of liquid cannabis.

District of Columbia: Up to 57 grams of marijuana or up to six plants.

What kinds can you buy? In Washington and Colorado, consumers can buy anything from marijuana flowers, to edibles like pot brownies, and highly-concentrated liquids and extracts. But in Oregon, only the flowers can be sold at dispensaries (although you can still make pot brownies in your kitchen).

Alaska is working out regulations that would allow consumers to buy buds, edible products or marijuana extract. Since you can’t technically buy it in the District of Columbia, only the plants are legal.

Loading... Loading... Loading... Loading... Loading... Loading...

Packaging ranges from state to state. In Washington, each marijuana producer has its own unique brand. In Colorado, where all marijuana products must be stored in child-proof containers, packaging company Kush Bottles has developed a whole line of jars just for marijuana retailers.

How strong is it? The THC content of cannabis flowers typically ranges from about 15 to 25 per cent. At Uncle Ike’s Pot Shop in Seattle, a blend called Harlequin Tsunami has a THC concentration of just 10 per cent and offers “potent relaxation with minimum psychoactive properties.” On the other end of the spectrum, OG Chem promises to “turn your brain into a science experiment” with a heavy 30 per cent THC concentration.

Most states have laws regulating how concentrated liquids, edibles and extract can get. In Alaska, regulators have proposed that no product can have a THC concentration higher than 76 per cent and single-servings of edibles cannot have more than 5 milligrams of THC.

Other restrictions: Even in states that have legalized marijuana, it’s still illegal to consume marijuana in public. And it’s always illegal to drive under the influence.