If you are requesting them for someone else then you need a notarized consent document.

If you are requesting them for yourself then you still need a notarized document, where you basically affirm that you are yourself and want your own documents. It's a little strange, I know.

Click on the 3rd link I provided, scroll down to Appendix B, it has a sample of the document I'm talking about, however that one also includes parts about letting someone else access them.
Sample without that parts, where you want your own documents, would be something like this:

Affirmation of Identity {centered, bold}

This is to affirm that
I, [Name here] request access to records maintained by U.S. Customs and Border Protection which pertain to me.

My present address is:
[address here]

My date of birth is: [DOB here]
My place of birth was: [city, country of birth here]

I understand that knowingly or willfully seeking or obtaining access to records about another person under false pretenses is punishable by a fine of up to $5,000. I also understand that any applicable fees must be paid by me.

I request that any located and disclosable records to be forwarded to me, at my present address listed above.

I hereby certify under the penalty of perjury that the foregoing is true and correct.

Executed on ___________________ {date, don't put it in until you're at the notary}.

_______________________________________________ {sign here once the notary instructs you to do so}
(Signature of Affirmant)


[ ] - Wildcard, put whatever applicable info there, e.g. [Date of Birth here] becomes, for example, March 2nd, 1988.
{ } - Comments, this is just to clarify a field, leave this out of the actual document