Well Trump’s police state is happening. Free travel looks to be gone. Travel in New Mexico highways you can be stopped and asked “are you a US citizen”. This is the equivalent and is of “show me your papers”.
I assume ICE will expand this into the Northern states soon. Let’s face it New England is smaller then Texas so no reason not to do it. Not sure about New Mexico maybe size of Maine (will google it later) Equal protection I would think would mean all parts of US has to be treated the same.
The woman needs to sue the Border Patrol for hindering her right to free travel without proving citizenship. Its not like a checkpoint for drunk driving since drunk driving is illegal.
If she was travelig from Mexico to US it would be fine to ask at a border checkpoint. Withen the border? Nope. You should never be asked.