The title itself is an oxymoron. Why? Well, let’s hypothetically say a large number of people decide to protest openly against a policy or policies deemed as oppressive or an infringement on the rights of protesters, how can one protest it “legally”? If the beholders of the powers that be, known as the “authority” establish policies that are then protected by the force of “Law”, then one must theoretically accept the laws because they are, well, the law of the land. But if a group feels a policy or law, or even a regulation is oppressive, what makes you think the lawmakers would also see it as oppressive?
As long as the beholders of the powers that be do NOT see the laws as oppressive, which they usually do not since it does not affect them, then any protest against the “Law” would be a threat to the system that has established and set the laws and policies that be. In other words, you can deem a law or system to be oppressive, but in order to “protest” against the laws, you need “permission” from the law. That’s like filing a complaint about your neighbour then being forced to ask the neighbour if you can file a complaint against them. If you have, in fact, asked the neighbour if you can to complain, or for our argument’s sake to “protest”, it’s legal. But if you don’t ask them if it’s okay to protest against their conduct, it’s illegal. See the absurdity?
The fact of the matter is there is no such thing as a truly “legal protest”. All true demonstrations where the aim is to change the laws that be can only come through “illegal protest”. For a protest to be legal, it would have to be in agreement with the laws. Thus, any action taken (ex. public protest or demonstration) to change those laws would be counter to the law and therefore, illegal.
So, if a government proclaims that a protest is “illegal”, it doesn’t mean anything. It just means that the protesters have not prearranged an agreement with us to coordinate and guarantee that their demonstrations will not interfere, disturb and/or threaten in anyway the policies and regulations established within the system. If the protesters do ask for this permission, then what is the point of protesting in the first place?