Chicago (CBS) -- With more than two dozen flights per day, thousands of passengers are flying into O'Hare and Midway from LAX over the long weekend.
But this year, the rules are a little different in California than they are in Illinois.
LAX posted a policy on their website allowing passengers to travel through the airport and on to their destinations with as much as "28.5 grams of marijuana and 8 grams of concentrated marijuana".
But according to Chicago police, what's legal while boarding in the Golden State suddenly becomes illegal upon landing in states like Illinois where recreational pot is not allowed.
"I would think at the gate maybe when you depart, they'll have say 'I just want you to know it's illegal when you land'," Larry Stech, who flew into Chicago from LAX, said.
In a statement, TSA told CBS 2 they're more focused on explosives and weapons. But if TSA officers come across drugs in the course of their work, they contact CPD.
"I don't know how they are going to deal with the issue," Matt Sutton, another passenger who flew in from California, said.
CPD said passengers from California and the nine other states with recreational weed don't get a pass.
CBS 2 dug into the numbers and, if cannabis is moving through Chicago's airports, the number of actual arrests is pretty low.
Last year, CPD was called to handle 36 narcotics cases at O'Hare and 23 at Midway. Four arrests were specifically for passengers found with more than 30 grams of cannabis and another arrest was for less than 30 grams.
Passengers returning from California Friday said the rules are confusing and that something needs to change.
"There's not a good answer," Sutton said. "I've got my own personal opinions on what I think, but until the states decide on what they want to do along with federal law, there's going to be tricky situations all the time."
So far this year, police have made 25 arrests at O'Hare and Midway for passengers allegedly carrying drugs.
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