Information on penal codes, also referred to by criminal codes, is accessible through the Legal Information Institute on the Cornell University Law School website. Each state is responsible for writing and enforcing its own codes, therefore each state's codes vary, as explained on Wikipedia.
The Cornell University site displays these codes indexed alphabetically, by state. Washington, DC, Massachusetts, Montana, Pennsylvania and South Carolina criminal codes are not included on the table provided by the Legal Information Institute. Information about penal codes for those states must be gathered on each state's individual website. For example, to explore the penal codes employed by Washington D.C., researching "Title 22. Criminal Offenses and Penalties," of the Code of the District of Columbia is required, as it is not compiled elsewhere.
Penal codes are a code of laws relating to crimes and offenses, and the due punishment for those crimes, states Lawyers.com. An example of a penal code is CA Penal Code 215, the California law about carjacking. The first part of code 215 is the state's definition of carjacking. In this case, it is generically defined as removing the possession of a car from a driver or passenger with force and the intent to deprive them. The second part of the code outlines possible punishments, including fines, prison and probation, as explained by Esfandi Law.