Forgery is considered a felony conviction in the State of Washington under RCW 9A60.020, falling under the category of white-collar crimes. Use this instruction for making, completing, or altering a written instrument, which is only one of the ways of committing forgery.Forgery under Washington law is a class C felony. What is the Punishment? Forgery is considered a felony in all 50 states and Washington is no exception. The law defines forgery as the making of a fake document, the modification of an existing document, or the unauthorized signing of a signature. Under Washington state divorce laws, adultery (or any other marital fault) doesn't factor into a judge's decision regarding whether to award alimony.