Let's say that you get stopped on a routine check by the police while driving. You do not have your driver's license on your possession. Driving without your license is not illegal, but it is likely that you will be asked to prove that you do indeed have a valid driver's license within a certain time-frame, or face a fine. Driving with no valid license whatsoever is always illegal, however, and carries serious consequences.
It is illegal to be driving without a valid license for many reasons. It goes without saying that if you do not have a valid license or if you have had your license revoked for drunk driving or another traffic violation, you should not be on the road. As a driver without a valid license, you run a much higher risk of injuring yourself or others, and this is why there are such serious penalties for doing so.
The consequences of driving without a license are determined from state to state. The seriousness of the offense is usually determined first of all by the reasons why you do not have a valid driver's license. It could have been because your license recently expired, or it could have been revoked because of dangerous driving - there is a big difference under the law. The seriousness of the crime will also be judged by whether this is your first offense or not.
If you have been caught driving without a license, it is important to not be complacent about such a charge. Do your research to figure out the best way forward.
Source: FindLaw, "Driving without a License," Oct. 27, 2017