Mass. Gen. Laws ch. 149 § 66
A person shall not employ a child or permit a child to work in, about or in connection with any establishment or occupation before 6:00 a.m. or after 10:00 p.m.; provided, however, that a child may be employed as an operator in a regular service telephone exchange or a telegraph office until, but not after, 11:00 p.m.; provided, further, that a child 16 years of age or older may be employed until, but not after, 11:30 p.m. on any night other than a night preceding a regularly scheduled school day; provided, further, that a child 16 years of age or older may be employed in a restaurant or race track until, but not after, 12 oclock in the evening on any night other than a night preceding a regularly scheduled school day; and provided, further, that an establishment which stops serving clients or customers at 10:00 p.m. may employ a child until, but not after, 10:15 p.m. A person shall not employ a child or permit a child to work in, about or in connection with any establishment or occupation after 8:00 p.m. unless the child is under the direct and immediate supervision of an adult acting in a supervisory capacity, who is situated in the workplace and is reasonably accessible to the child. This section shall not apply to a child employed at a kiosk, cart, or stand located within the common areas of an enclosed shopping mall that employs security personnel, a private security company or a public police detail every night from 8:00 p.m. until the mall is closed to the public.
Mass. Gen. Laws ch. 149, § 66