Step 1: Understand the context: Private International Law.
The Doctrine of Renvoi is a concept used in Private International Law (also called Conflict of Laws) when a court has to decide which country's law to apply to a case involving foreign elements.
Step 2: Define Renvoi.
"Renvoi" is a French word meaning "sending back" or "referring back.
" The doctrine works like this:
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A court in Country A's rules direct it to apply the law of Country B.
When the court in Country A looks at the law of Country B, it finds that Country B's rules direct it to apply the law of Country A.
This "referral back" from Country B's law to Country A's law is the core of the doctrine.
In essence, the court in country A, after being directed to a foreign law, is then referred back to the law of its origin (its own law).