I have a friend who travels back and forth from Europe to the States quite often. She is always hassled and threatened to be sent back coming through US Immigration. She has dual French and Norwegian citizenship. She has always used her French passport because that is where she has lived for 10+ years.
My question is would it be possible for her to use her Norwegian passport next time to avoid being stopped at immigration because she has never used that passport to come into the States? Or does that not matter and CBP tracks her moves whether she uses her French or Norwegian passport? She has never overstayed her visa-free admission period of 90 days in the US, but they still threaten to send her back every time, she is just trying to avoid this.