Let me give you the definition of forgery according to the New York Penal Code:
A perosn is guilty of forgery when, with intent to defraud, deceive or injure another, he falsely makes, completes or alters a written document.
Since your husband put in your name into the up to then "incomplete" money order, he "completed" it.
The law further says: A person "falsely completes" a written instrument when, by adding, inserting or changing matter, he transforms an incomplete written instrument into a complete one without the authority of anyone entitled to grant it...
In New York what your husband did would be a felony and so is the use of such an instrument, that crime is called "criminal possession of a forged instrument."
The question of proving that it was a "forged" instrument of course is another matter. That is what the prosecution has to do.
