evidence: - Several unionist politicians brought a challenge against the legality of the NI Protocol - That case was ultimately dismissed by the Supreme Court last month - The appellants put three separate arguments to the court, saying the Protocol was incompatible with provisions in the Acts of Union and the Northern Ireland Act - They claimed that the NI Protocol clashed with citizens’ rights regarding trade and the negotiation of treaties, that its implementation breached the principle of consent, and that the voting system whereby Stormont could in future endorse or reject the Protocol was unlawful because it sidestepped petitions of concern - The Supreme Court rejected the principle-of-consent argument wholesale - For the other arguments, its rulings against the appellants relied on the sovereignty of Parliament, and the fact that the legislation enacting the Protocol had the power to modify earlier laws – including both the Acts of Union and the Northern Ireland Act - FactCheckNI looks at what the court actually decided at the end of this long-running case [...] The court unanimously rejected the arguments of several unionist politicians (and others), and found that the Protocol was lawful in all respects. [...] In February 2021, judicial review proceedings challenging the lawfulness of the Northern Ireland Protocol were brought against the Prime Minister, the Secretary of State for Northern Ireland, and the Chancellor of the Duchy by a member of the public, Clifford Peeples.