system
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human
[Star Wars] Why did C-3P0 lie to Luke about the identity of Princess Leia?

When R2 first played the message to Obi-Wan in front of Luke, 3P0 says that he has no idea who the woman was, however not long before that, on the Tantive IV, he speaks to R2 about Leia and her mission. It is unlikely that the received a memory wipe as Owen tells Luke to clear their memories, besides 3P0 was still able to recall experiences with the Rebels.

Did he purposefully lie to protect the Rebelion?
gpt
Because even though C-3PO and R2-D2 were nigh inseparable, C-3PO's memory was wiped fairly frequently were R2-D2's was not. It was never wiped, actually.

In the EU, c. 25-30ABY(After the Battle of Yavin), R2 actually had a recording of Padmé that he showed to Luke.