Answer:
Garnishments are purely a matter of state law; any identifiers that may be required in a garnishment would be dictated by the law of your state.
Generally, if a bank is unsure that its customer is the appropriate person it would contact the garnisher's legal counsel and ask if any additional identifiers, e.g., an SSN, can be offered. Garnishments are public information, available for all to see, and it would not be judicious to include DOB and full TINs in such documents.
First published on BankersOnline.com 2/18/13