It is perfectly within a TSA agents job and rights that if they find someone transporting something that could be reasonably believed to be at least $10,000 to question the passenger at the very least if they are travelling internationally, and if they have documented the transport of the cash.
He is not talking about the TSA or leaving the country, he is talking about the police seizing large amounts of money in traffic stops, even when there is no evidence of a crime. Once they seize the money, you have to sue them to get it back. Since this is civil forfeiture, you do not have the same rights as if you were charged with a crime. The police sue the property itself. Perhaps the lawyers at Cornell put it better:
Unlike criminal forfeiture, civil forfeiture proceeds against the property, not the person.
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Due to its civil nature, the roles of the parties change. Instead of prosecutor versus defendant, the hearing concerns a plaintiff, the United States in the case of Federal forfeitures, and a defendant, the property in question. The owner is effectively put in the position of being a third party claimant. Furthermore, civil hearings involve a more lenient burden of proof than "beyond a reasonable doubt." Once the government establishes probable cause that the property is subject to forfeiture, the owner must prove by "preponderance of the evidence" that it is not.
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Unless provided in statute (as in 18 U.S.C. 981(a)(2)), innocence of the owner is typically not a defense.
There have been many cases where money was seized without any evidence of a crime (here is a book about some of them). There is a clear incentive for police to seize money in this manner as they generally get some or all of the seized money to use for departmental operations. This behavior by law enforcement directly contradicts the text of the fourth amendment, another casualty of the drug war.