Driving without a license if an infraction in most states - i.e. the penaly is a simple fine.  However, if the crime is a misdemeanor in your state, then the exposure is simply a higher fine or has worse implications as it  results in you having a criminal record.  whether or not your wife gave you the keys is irrelevant.  if you drove without a license, then you are guilty.  However, your wife's words alone may not be enough to convict you if the police didnt see you.