The law in most states provides for immediate DUI license suspension and confiscation of the license if the breath test result is above the legal limit (or, in the case of a blood or urine test, if the officer reasonably believes the result will be above the limit). To answer your direct question, a driver’s license is a privilege, not a constitutional right, and handing you a suspension does not amount to a criminal conviction. So your rights to be presumed innocent were not violated.
The presumption of innocence does not apply to every occasion that you come into contact with the law; only in criminal cases where you could be punished by imprisonment or fines. There are many other laws which require you to do things or not do things which are not criminal laws. For example, there may be an ordinance forbidding you from having a neon sign on your house in a residential neighborhood, but you are not presumed innocent of violating the ordinance.
It is the same with a driver’s license administrative action. The suspension is not even coming from the Court, but from the Department of Motor Vehicles, with the officer as its agent to serve it upon you. You can demand a hearing to challenge whether the officer was correct to do this, and that hearing is before the DMV, not the Court.
Drunk driving laws vary depending on what state you live in. To find out more about the DUI laws in your state click here.
Related Articles:
First DUI: What You Should Know
Understanding a DUI Driver's License Suspension