Genesis Hansen is an Oregon State University student who was riding her bicycle through Corvallis during the fall semester when she saw blue lights behind her. So she stopped her bicycle and waited. The police officer told her she’d been riding on the left side of the road, which is against state law. Then the officer told her he was carrying out a traffic stop so she’d need to present her driver’s license. Because she wasn’t driving, she refused–and Genesis was arrested for not showing her ID.

The truth is that in every state, police can stop a bicyclist if they suspect the rider has broken a law (be it a traffic law or stealing the bike). The gray area is that in some states this may not be considered a “traffic stop” like when traffic police stop a vehicle, and this may change your rights.

The Oregon District Attorney later dropped the charges against Genesis, ruling that the original arrest had been unlawful. But in a different state, it would have been a different story. The Bicycle Law website explained that in California bicyclists may not need to have a driver’s license to ride a bike, but if anyone is stopped for a traffic violation they will need to identify themselves to the police. They could hand over a different form of documentation, such as a state ID or a passport card. But the police do need to know who they are dealing with.

Honestly, this law makes some sense. If you are jay walking, and a police officer (whether in a car or on foot) tickets you for it, they’ll ask you for ID before they write out the ticket. Why should a traffic violation while on a bicycle be any different?

Many bicyclists report having been pulled over by the police. Why? The reasons for these stops are as varied as the states they hail from.

Reddit User ZeusTheMoose reports that they were bicycling home from work, stopped for some groceries, and then immediately had police parked in a squad car flash their lights. When the rider stopped, the officers explained that you can’t bicycle at night without a taillight. The rider was confused until they realized the groceries on their rack were blocking their taillight.

The laws around night time lighting on your bicycle vary by state–and even by municipality. So it’s important to know what the local guidelines are.

A Quora user named Bob Steinberg reports that a pair of police officers in a squad car actually pulled a U-Turn to tell him he’d crossed into the wrong (left) lane while navigating a lefthand turn in an intersection. He explained he didn’t have any ID On him and they let him go with a warning.

Next, find out whether bikes and e-Bikes are actually always allowed a full lane.