The Federal Reserve Did It
A lot of people are deeply suspicious of the Federal Reserve system, which tinkers with interest rates and the availability of money to lend stability to the U.S. economy. Or at least, that's what the Trilateral Commission, the Knights Templar and the Masonic elders want us to think. (Before they put out a hit on us, we should emphasize that we're just kidding).
So it's not too surprising that conspiracy theorists would posit that the Fed had a role in JFK's murder, as well. Some have suggested JFK ran afoul of the central bankers by issuing Executive Order 11110 in June 1963, which would have taken away the Fed's power to allow the U.S. Treasury to bypass it and issue paper currency backed by silver. This supposedly would have eliminated the demand for federal notes but vastly reduced the U.S.'s national debt [source: Rense.com].
Or maybe not. For one thing, silver certificates, as such paper currency was called, already existed. For another, JFK actually wanted to get rid of silver certificates, and had just signed a bill passed by Congress that allowed the government to melt down its silver reserves and use the metal to make coins. To ease the transition, JFK issued the executive order in question, which allowed the government to keep printing the certificates for a while longer [source: Associated Press]. Finally, none of this really had anything to do with the Fed.