a law enforcement officer within the meaning of section 5541(3) and to whom the provisions of chapter 51 apply;

a member of the United States Secret Service Uniformed Division;

a member of the United States Park Police;

a special agent in the Diplomatic Security Service;

a probation officer (referred to in section 3672 of title 18); and

a pretrial services officer (referred to in section 3153 of title 18).