Mass. Gen. Laws ch. 201A, § 13: Powers of custodian

Section 13. (a) A custodian, acting in a custodial capacity, has all the rights, powers, and authority over custodial property that unmarried adult owners have over their own property, but a custodian may exercise those rights, powers, and authority in that capacity only.

(b) This section does not relieve a custodian from liability for a breach of section twelve.