According to the Benton County Sheriff's Office the "White Rabbit" brand of synthetic marijuana contains an analog of a schedule one narcotic, which makes possession of the substance a felony.
Sergeant Michael Wedgewood says K-2 was no secret when it first showed up in head shops and gas stations across Benton County.
"They packaged it out in the open, it was K-2 synthetic marijuana," he says. "They were very up front about what it was for."
But when states and the county started cracking down, the manufacturers got creative.
"They started making the packaging a little different to make it seem like oh this is legal," he says.
Wedgewood says the changes aren't just cosmetic. New chemicals are showing up in lab tests.
"These products are ever changing because they're going to stay one step ahead of the law if they can," he says. "That's how criminals work."
Doctor Katherine Barton of Northwest Health System says people can't trust the packaging, because regulations on herbal supplements are lax.
"We have no idea what people are putting in these things," she says. "You don't have to prove to anybody what's in it, and you don't have to prove that it's safe."
Barton says jail time is nothing compared to what could happen.
"You're risking your life," she says. "If you don't know exactly what it is you're putting in your body, then don't put it in your body, because you may not survive."