Is Illegal Assembly Allowed Now?

I am wondering why the 5000 odd UiTM students were allowed to assemble illegally when they march to hand the memorandum protesting Tan Sri Khalid Ibrahim's statement asking for UiTM to open 10% of its intake to the other races. The illegal assembly was held in front of the state secretariat but why are they allowed and do they have a permit for the illegal assembly? If no permit were given then PDRM is stamping its double standard. Just because the students are showing their protest to the government, they are given the green light to go ahead. However if the protest is organised by the ruling party (I mean Pakatan Rakyat) to protest against the opposition (I mean BN) then there will be water cannons and FRUs and maybe the leaders who organised the illegal assembly will be hauled up. Why the double standard?