Residents of California enjoy the protection of a statute of limitations against legal actions to collect a credit card debt after a certain number of years have passed. This is meant to prevent creditors from pursuing unfair cases in which too much time has gone by for the accused debtor to properly be able to assemble the evidence for their defense.
State law sets the expiration date for debt at 4 years. After that point the credit card agency may still attempt to collect on the debt, so long as they do not violate any state or federal statutes governing creditor harassment. However, they may not sue to collect upon it and any such case should be dismissed upon the revelation of the age of the debt.