(a) A person may not engage in any form of picketing activity in which a picket constitutes any character of obstacle to the free ingress to and egress from an entrance to any premises, either by obstructing the free ingress and egress with the person's body or by placing a vehicle or other physical obstruction.
(b) In this section, "picket" includes a person:
(1) stationed by or acting for an organization to:
(A) induce anyone not to enter the premises being picketed; or
(B) observe the premises being picketed to ascertain who enters or patronizes the premises; or
(2) who follows employees or patrons of the premises being picketed to or from those premises to observe them or to attempt to dissuade them from entering or patronizing the premises.