You may drive directly to a repair shop (less than 1 mile) under extreme caution, but police may still ticket you. For longer distances, do the following:
While it is not always illegal in the strictest sense (depending on local laws regarding rear visibility), driving with a shattered back window is reckless. It compromises the structural safety of your vehicle, exposes you to harmful fumes, and puts you at risk of a traffic citation. can i drive with a shattered back window