U.S DEPARTMENT OF HOMELAND SECURITY HAS TOLD BANKS - IN WRITING - IT MAY INSPECT SAFE DEPOSIT BOXES WITHOUT WARRANT AND SIEZE ANY GOLD, SILVER, GUNS OR OTHER VALUABLES IT FINDS INSIDE THOSE BOXES!

http://oregonrepublic.posterous.com/us-department-of-homeland-security-has-told-b

I do know banks can deny customer access to safety deposit boxes.  I am not sure of the implications of the Patriot Act, but I wouldn't be surprised if this is true.  Readers should perform their own due diligence, as will I.