SECTION 1.   Chapter 268 of the General Laws is hereby amended by adding after section 21A, as so appearing, the following paragraph: -

Section 21B.  Any person who is employed by or contracts with any public or private school, or any institution of higher learning, or the department of youth services, the department of social services, the department of mental health, the department of developmental disabilities, or any private institution providing services to clients of such departments, and who, in the course of such employment or contract or as a result thereof, engages in sexual abuse of a person under the age of 18 who is served by such school, department or institution, within or outside of such school, department or institution, shall be punished by imprisonment for not more than five years in a state prison or by a fine of not more than $10,000 or both. In a prosecution commenced under this section, an individual served by such school, department or institution shall be deemed incapable of consent to sexual relations with such person. For purposes of this section, sexual relations shall be defined as that term is used of chapter 260,  section 4C.