service of subpoena
is a subpoena served by the Special Commissioner of Investigation for the NYC School District which has subpoena power thru NYC Charter chapter 34 and Exuctive Order 11 valid to a non-employee of the School District or a vendor doing business with the School District ? (ex a doctor for a doctor's note for a teacher or a hotel guest list where a teacher stayed)
Re: service of subpoena
Such subpoenas are indeed valid for non-employees; perhaps the only example you list that would arguably be privileged is the doctor. Generally, in NY an attorney can issue a subpoena, or an elected agency head; however, under normal circumstances a court must "so order" a subpoena for hospital records, or one served on a city agency.