Final answer:
The school nurse's legal responsibility when suspecting child abuse is to report the suspected abuse according to state regulations. It's crucial to document observations, but contacting the parents or discussing it with school staff before making a report is not advisable.
Step-by-step explanation:
When the school nurse suspects that Johnny is being abused due to patterned bruises, the nurse's legal responsibility is to report the suspected abuse according to the state's regulations. This often requires notifying child protective services or law enforcement, regardless of the setting, whether it's an educational institution, medical facility, or elsewhere. It is part of a mandated reporter's duty to report such suspicions and ensure the safety of the child.
In addition to reporting, documentation of observations in the medical record is crucial. It is not appropriate to call the child's parents about the suspicion as it could put the child at further risk, nor is it appropriate to discuss the findings with the child's teacher, principal, or school psychologist without first ensuring the report is made according to legal obligations.