A Government authority may obtain financial records under pursuant to judicial subpena only if—

((1)) such subpena is authorized by law and there is reason to believe that the records sought are relevant to a legitimate law enforcement inquiry;

((2)) a copy of the subpena has been served upon the customer or mailed to his last known address on or before the date on which the subpena was served on the financial institution together with the following notice which shall state with reasonable specificity the nature of the law enforcement inquiry:

((3)) ten days have expired from the date of service or fourteen days from the date of mailing of the notice to the customer and within such time period the customer has not filed a sworn statement and motion to quash in an appropriate court, or the customer challenge provisions of have been complied with.