So can I wake up on January 1 and walk down the street smoking a joint?

Nope. Under the Cannabis Regulation and Tax Act, you’re not permitted to consume cannabis in a public place — on the street, in a car, in Millennium Park, wherever. Think about it like alcohol: You can’t walk down the sidewalk in Chicago sipping a beer, right?

So will I be arrested if I’m blazing up outside?

Police can stop you, but whether you can expect just a ticket or an arrest is not clear. Right now, a punishment for this violation is not laid out in the statute, and police have yet to determine what the penalty will be.

Can I even be high in public?

Yes! Unless your behavior is such that you’re violating some other law. Like if you’re so high you feel the need to take off your clothes, you can be arrested and charged with disorderly conduct or public indecency.

What about driving while high?

The law on this is a mess. You’re not allowed to operate a motor vehicle with more than five nanograms of THC per milliliter of blood or 10 nanograms of THC per milliliter of any other bodily substance such as saliva or urine, but there’s currently no standardized roadside test to determine whether drivers are impaired. And even the blood test is a big problem, because the presence of THC doesn’t prove impairment, since the drug remains in the bloodstream for a few days or even a few weeks after you use it.

So there’s no such thing as a weed Breathalyzer?

There are companies developing cannabis Breathalyzers that purport to measure cannabis use within the preceding few hours, but they’re not currently in use in Illinois. Some police forces test a saliva swab from the driver’s mouth to find out if any drugs are present in the person’s system in order to give probable cause for an arrest. And in Illinois they’re training drug recognition experts in detecting impairment through a bunch of tests beyond the typical field sobriety test: pupil dilation, eye tracking, and vital signs such as blood pressure, temperature, and pulse rate.

What if I want to get high and ride my bike?

Practically speaking, how the hell is anyone going to know? The cops aren’t going to say, “Hey, you with the bike — stop! You must’ve eaten a weed gummy! You look too happy!”

My employer drug-tests new hires. Could they fire me if they find THC in my system?

Yes. The legislation specifically allows employers to run their businesses the way they want. Even a medical cannabis card doesn’t protect you from employer rules. But fewer employers in legal states are testing for cannabis.

I’ve got a friend in Wisconsin. Can I bring him some weed I bought legally here?

As soon as you cross the border, you’re in violation of Wisconsin law, so you can be pulled over and prosecuted.

There’s a lot of winter left, and I want to stock up. How much weed can I buy?

If you’re 21 or older, you can lawfully purchase and possess 30 grams of marijuana flower, five grams of concentrate, such as vape oil and dabs, and 500 milligrams of THC in an edible or other product. It’s half those amounts if you’re not a resident of Illinois.