carrying cash
My son's boss has him to fly from CA to TN to purchase a car for him. His is giving him $50,000 cash so there is not a paper trail of the purchase; I suspect he hasn't claimed this as income along the way...am I doing something illegal?
Re: carrying cash
Go to the ACLU website (http://aclu.org/safefree/general/39926prs20090618.html) for a very recent case and an interesting audio recording. There are many reports of people being hassled or even detained by the TSA just for carrying large amounts of cash. If you carry large amounts of cash on domestic airlines, you are not required to answer questions about it.
Re: carrying cash
If that's truly what you're doing, then no, it's not illegal to buy a car with cash.
I'm guessing there's much more to the story than just this.
If he's caught with $50,000 in cash and no good explanation, expect the money to be confiscated and your son to be detained while they sort this out.