In general, I believe for example the US court system hierarchy (where you appeal instance by instance in serial order) is very different from the EU court system (when it comes to interpretation on EU law).
Lower courts MAY ask the EU court for guidance on what EU law means while the court of last instance for a type of case (the highest court) MUST ask the EU court on what the EU law means if it is not clear.
Here is the relevant text in the Treaty of the Functioning of the European Union (TFEU):
If anyone is interested in more information of exceptions from referring to the EU court you can read up on the doctrine of acte clair and acte eclairé. This doctrine is now always followed (nd may sometimes be difficult to follow) by court of last instance so it is important that lower courts can ask if they think the higher court has made an error in relation to this.
It is similar how you can move constitutional questions from state to federal court in the USA, with the main difference being that EU does not have federal circuits of courts like USA does, but effectively only a supreme court.
In general, I believe for example the US court system hierarchy (where you appeal instance by instance in serial order) is very different from the EU court system (when it comes to interpretation on EU law).
Lower courts MAY ask the EU court for guidance on what EU law means while the court of last instance for a type of case (the highest court) MUST ask the EU court on what the EU law means if it is not clear.
Here is the relevant text in the Treaty of the Functioning of the European Union (TFEU):
https://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX...
If anyone is interested in more information of exceptions from referring to the EU court you can read up on the doctrine of acte clair and acte eclairé. This doctrine is now always followed (nd may sometimes be difficult to follow) by court of last instance so it is important that lower courts can ask if they think the higher court has made an error in relation to this.