On October 21, a trooper with the Texas Department of Public Safety pulled over a speeding vehicle just outside Amarillo. The driver was on I-40, the east-west highway that cuts across the southern half of the country, including straight through the state’s panhandle.

Local news outlet KFDA said that the trooper reported “signs of illegal activity” while performing the traffic stop.

Likely using the “probable cause” search, the DPS trooper found nearly six pounds of cocaine in the car.

This amounts to about $260,000 dollars-worth of the substance.

The officer arrested the driver. Due to the sheer weight of cocaine in the vehicle, authorities charged the driver with intent to distribute.

Defining “signs of illegal activity” during a traffic stop can be difficult since it’s fairly open-ended in terms of interpretation. Physical evidence in plain sight is certainly a qualifier for a search based on “signs.” However, depending on an officer’s experience, training, and even personal execution of job duties, there are a variety of other qualifiers.

A slew of law firms say that police officers can flag intangible observations, like visible behaviors. Odors and even inconsistencies in a driver’s story can “justify” further investigation, including a vehicle search based on “probable cause.”

In this case, the DPS trooper might have observed anything from “questionable” behavior, like erratic movement or inability to speak clearly. Otherwise, the police officer might have even seen physical evidence of an illegal substance, including cocaine, in plain sight.