The Licensing Board can discipline a California nurse if he/she engages in unprofessional conduct. “Unprofessional conduct” includes: incompetence or gross negligence, using drugs illegally or in a way that threatens the public, being convicted of certain kinds of crimes (but criminal charges alone are not enough for disciplinary action), engaging in certain kinds of fraud, being disciplined by a board in another state, and being careless with respect to blood-borne diseases.