on third thought, it must have been the public works protection act that i'm thinking of, or some case that cited it.

in the public works protection act (which was in force over the winter of 2012-2013, but has since been repealed),

1) there is a reference to

any railway, canal, highway, bridge, power works including all property used for the generation, transformation, transmission, distribution or supply of hydraulic or electrical power, gas works, water works, public utility or other work, owned, operated or carried on by the Government of Ontario or by any board or commission thereof, or by any municipal corporation, public utility commission or by private enterprises,

....as being a public work, which is the collection of things i remember.

2) "any provincial and any municipal public building" is covered as a public work, which would include city hall.

3) a guard or peace officer (not even a cop!):

may search, without warrant, any person entering or attempting to enter a public work or a vehicle in the charge or under the control of any such person or which has recently been or is suspected of having been in the charge or under the control of any such person or in which any such person is a passenger;

...which is what i was trying to get across.

4) A guard or peace officer may arrest, without warrant, any person who neglects or refuses to comply with a request or direction of a guard or peace officer, or who is found upon or attempting to enter a public work without lawful authority

============

so, this is the law i cited to the food not bombs kids to try to make them understand the danger they were in serving at city hall, which they naively thought they had special rights at because it was "public property", i'm certain of it.

but there is no reference to terrorism. that must have been case law. let me find that....