My rehearsed line is “you in the <distinctive clothes> I’ll split the settlement with you if you record this and call a lawyer!”
Gotta disrupt the bystander syndrome by calling out a particular person
And provide the financial incentive
In addition to calling several high profile agencies like ACLU and EFF, I would call one or two local lawyers and say,
"Hi, my name is FirstLast, at 2:05 PM I was at LAX Terminal 2. A man wearing XYZ was being led away by CBP agents and was pleading for someone to call a lawyer. Is this something you can handle? I imagine you can get in contact with LAX authorities if you are interested in taking this case."
I guess it's different at the federal level because they can detain people longer and with less cause, but eventually I believe they have to be offered the right to legal representation and being hauled in front of a judge publically.
Unless of course the US Govt wants to extradite you from LAX to Guantanamo, at which point a lawyer is the least of your worries.
Ive never made it to the nightly news with a video of me shouting that line
Or on a talk show about the lawsuit for that recorder to get their share of a settlement
So not sure why to tell you