It's people who rape people, murder people, poison people... oh wait, they're all illegal too.
The US is a uniquely litigious country so going through the court system in an adversarial sense makes perfect sense. In The UK system you might instead ask a court to determine who or which state organ has responsibility to fix the problem or who has authority to do something. See for instance the judgement on the Brexit case: https://www.judiciary.gov.uk/wp-content/uploads/2016/11/judg....