i wrote to laura bush regarding my N-400 and was stuck in name check. then i received this letter from dept of justice and a form with reference number so i sign and notorised the letter to FBI and they have send a copy to Mr. cannon, this is regarding name check status i was not even fingerprinted because they told me that they have my fingerprint from I-751.
I forgot to mention that, with every inquiry letter that I sent to various politicians, I included a signed statement authorizing them to obtain case information on my behalf. If you haven't included a similar statement with your correspondence, chances are they sent you this form for that exact reason.
If I'm not mistaken, most politicians request that release before making inquiries on your behalf.