So how exactly does this "Charter of Fundamental Rights of the European Union" work? Wikipedia says > European Union must act and legislate consistently with t

So how exactly does this "Charter of Fundamental Rights of the European Union" work? Wikipedia says > European Union must act and legislate consistently with the Charter and the EU's courts will strike down legislation adopted by the EU's institutions that contravenes it. So somehow it constrains EU institutions, but not EU member states, somewhat like the US Bill of Rights before the 14th amendment?