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Congress created the TSA to implement airport screenings. After a number of terrorist threats all airports over the years U.S. Airports are required to implement security procedures. These include the x-ray device and body searches including strip searched if necessary. The TSA has criteria for whom gets searched and also does random searches. They effectively have the ability to act as they deem appropriate.
In 1973 the 9th Circuit Court ruled in U.S. vs Davis, 482 F.2d 893, 908, that the TSA has the power to search essentially any way they choose. In this ruling the Court found "noting that airport screenings are considered to be administrative searches because they are conducted as part of a general regulatory scheme, where the essential administrative purpose is to prevent the carrying of weapons or explosives aboard aircraft."
Per the court's ruling The 4th Amendment protections against searches do not apply to TSA searches. The search of your daughter was not an illegal search.
The question is not whether entering or exiting the U.S. all passengers boarding flights originating in U.S. are subject to searches. Your daughter could have refused the search, but she would not have been able to board the aircraft.
I know this was not the result you wanted to hear but it the law and could save you the aggravation of hearing a judge quote you the same case law. I would ask that in rating please rate my work and not the fact the law is not in your favor.
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