The US under Jim Crow and segregation was also a liberal democracy and it required people disobey those laws they deemed unjust to help change them. Those people are considered heroes because we know those laws were unjust.
And this is my point: you're talking strictly about legalities and following the letter of the law, but deciding what laws are unjust and thus worth disobeying is a moral/political judgement that everyone would make.
If people want to protest a law through civil disobedience of that law they're free to do so, but also may suffer the legal consequences. It should also be done only when all other democratic forms of protest and petition have been exhausted, because that's how we keep our society from turning into chaos like we have right now in Ottawa, on Jan. 6th, and during the Floyd race riots.
But what the truckers and rioters have done isn't civil disobedience, the laws they're breaking have nothing to do with the laws/policies they're protesting. It's just angry people trying to cause chaos in order to blackmail the government into doing whatever they want, which is anti-democratic and shouldn't be tolerated.
This is the only way civil society works. I don't want to live in a 3rd world society where rule of law has broken down and violence and civil unrest is common and society is dysfunctional. Civil society works because we all agree to follow the law even when we disagree with it, and government is there to enforce it. Everyone thinks their cause is righteous. Ie. Quebec separatists have a choice of either accepting the results of a democratic referendum & continuing to peacefully protest or causing civil unrest/violence until they get their way.