For the first time in the state's history, Massachusetts' highest court established legal guidelines for the use of physical punishment on children by parents.

The Supreme Judicial Court said it's permissible to discipline a child by spanking, so long as "reasonable" force is used and the child isn't harmed. 

The court also reversed the assault and battery conviction of a man who was seen by police spanking his almost 3-year-old daughter near a bus station. 

Read more from WCVB:

Corporal punishment cases had come before the court in the past, but the justices noted that specific guidelines had never been issued for the parental privilege defense, leaving open the question of whether spanking was allowed under any circumstances in Massachusetts.
Writing for the seven-member court, Justice Barbara Lenk said two important interests needed to be balanced: protecting children against abuse; and avoiding unnecessary interference with the rights of parents to raise children as they see fit.
Spanking or other mild physical punishment was permissible if "the force used against the minor child is reasonable," and used for the purpose of "safeguarding or promoting the welfare of the minor, including the prevention or punishment of the minor's misconduct."
But the court made clear that force can never be used if it causes or risks causing any lasting physical or emotional harm, and concluded that the overall balance must always tip in favor of protecting children from abuse masking as discipline.

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