When? The last time anyone paid for anything with Federal Reserve credit or money.
"Federal Reserve notes represent a first lien on all the assets of the Federal Reserve Banks, and on the collateral specifically held against them
"The notes have no value for themselves, but for what they will buy. In another sense, because they are legal tender, Federal Reserve notes are "backed" by all the goods and services in the economy."
[link to ustreas.gov (secure)
The US treasury has it, right there in black and white. ALL goods and services in the economy are first leaned by the Federal Reserve.
I have proof, via non-endorsement and bank records that is not the case for me. Remember, it is all about what you can PROVE.
I can prove, with bank records, receipts and canceled checks that I have demanded Congress, the Banks and the Federal Reserve obey the law of the land, that being the Constitution and not the rules they make via endorsement and contractual agreement.
I have the protections of the law because I obey the law.