There is a fine line between probable cause and full-blown harassment, and the line is becoming thinner in states bordering those that have recently legalized marijuana.

According to a special report from the Seattle Times, columnist Matt Ironside and his wife recently had the displeasure of experiencing intense law enforcement tactics during a trip from Washington to Idaho.

Ironside says that on Interstate 86, just outside of Pocatello, Idaho, a state police cruiser tailed him for two miles before flipping on the old rearview red, white and blue.

They were being pulled over, but why?

What is interesting about this particular incident is that it doesn’t appear as if Ironside was speeding. He did not have a taillight out or any number of other minor traffic infraction the police typically use to justify pulling over a motorist. In fact, Ironside says that the only motive the officer had for stopping the couple was that he hesitated on a lane change, which caused his tire to cross over the centerline. “As it turns out, that’s all a curious trooper needs,” he writes.

Turns out that Ironside’s tire crossing over the median was just the technicality the cop needed to pull the couple over for what was really the problem: a license plate from a weed-friendly state.

In fact, Ironside says that after the officer approached the vehicle, the only thing he was interested in determining whether or not they were under the influence or in possession of marijuana.

Interestingly, Ironside admits he was shocked that the officer had absolutely no interest in whether anyone in the vehicle had been drinking booze, even though alcohol continues to remain the most widely used intoxicant on the American roadways. “I was not asked about alcohol, writes Ironside. “ I was not asked about prescription meds.”

The Ironsides were victims of profiling, and ultimately pulled over because they just so happened to live in a place where partaking in herbal refreshments is legal.

Even though the Ironsides’ managed to escape unscathed, that likely had to do with the fact that he hasn’t smoked pot since he was a 22-year-old college student.

However, for the many stoners living in the weed-friendly states of Colorado and Washington, he says it may be wise to start exercising a certain level of caution when travelling across state lines, and just to be safe, you may even want to consider leaving that fat sack of the green stuff at home when chartering into prohibition territories.