JOLIET, Ill. (CBS) — Come New Year’s Day, it will be a felony in Illinois to sell synthetic marijuana.

WBBM Newsradio’s Steve Miller spoke to an undercover detective in Will County, which has been one of the main fronts in the war on synthetic pot.

LISTEN: WBBM Newsradio’s Steve Miller reports

Dave Margliano retired three weeks ago as chief investigator for the Will County State’s Attorney’s office.

“Let’s face it. I’m not your typical undercover police officer,” Margliano said. “But fat, out-of-shape old guys need drugs, too, I guess.”

One of his final jobs was riding his motorcycle up to places like tobacco shops to see how synthetic marijuana was being sold.

He showed us his collection.

“This one, the Black Mamba – it’s basically a synthetic marijuana. Black Mamba is the one that they said, ‘Do not ride your motorcycle after you ingest this. You’ll never be able to do it. Drive your car.”

In an undercover buy on one occasion, Margliano says a store clerk urged him to evade a passing police officer as he attempted to get on his motorcycle.

“The one place, I acted so high and drunk when I went in, the guy took me by the arm, put my arm over his shoulder, walked me out – after he sold me the product – got me next to my bike and said, ‘Are you sure you can ride?’” Margliano said.

“And I said, ‘Yeah, I can ride.’ And he goes, ‘Wait, wait, there’s a cop car going by. Just wait a minute.’ And we waited for the cop to go by,” Margliano continued. “And he said, ‘OK, get on.’ And I got on and started the bike. And he said, ‘Are you balancing?’ And I said, ‘Yeah, I’m OK.’ He said, ‘All right. Get out of here.'”

So will tobacco and head shops automatically stop selling the synthetic marijuana on Jan. 1?

“They’re going to take it into the back rooms and they’ll sell it out of the back rooms, because they all have inventory of it,” he said.

Synthetic marijuana is typically sold as potpourri or herbal incense, but is readily available even in convenience stores and gas stations.

The statewide move to ban the substance has been dubbed “Max’s Law,” following a tragic crash in North Aurora.

Max Dobner, 19, bought synthetic marijuana at a west suburban mall and experienced a panic attack, with rapid heartbeat and hallucinations after using it. He drove his car at 100 miles per hour into a home in the far west suburb.

In fact, many experts have said synthetic marijuana is actually far more dangerous than real marijuana. Those who use the synthetic products can suffer seizures, hallucinations, tremors, paranoia, convulsions, high blood pressure and an elevated heart rate, according to Will County State’s Attorney James Glasgow’s office.

Anyone who sells synthetic marijuana could be charged with a Class 3 felony, and could go to prison for five years and be charged a $150,000 fine. Any illegal stock, and the entire shop where it is sold, could be seized.

Sale of more than 200 grams of synthetic marijuana could go to prison for 30 years and have to pay $500,000 in fines.

Simple possession of synthetic marijuana could result in Class 4 felony charges, which would mean three years in prison and a fine of up to $25,000.

In some jurisdictions, that means the penalty for synthetic marijuana possession could be far harsher than that for possession of the real thing. In several Illinois municipalities, most recently including Evanston, anyone caught with 10 grams of real marijuana or less will get just a ticket instead of being arrested and taken to jail.

A ban on synthetic marijuana started Wednesday in Chicago.

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