1. One needs to be deceased for 5 years before being put on currency. This law was broken.
2. Currency design is signed into being for ‘x’ years by law. Again, IIRC, the Franklin half dollar had a few more years to go before it either expired as a design or was renewed. Another law broken.
I might be off on number 2, but number 1 I am sure of. I don't have time to research now, but like all things Kennedy, they had there own set of rules.
I think that the law said (and says) that one must be dead for 5 years before appearing on currency unless the president waives the restriction. And if the law has no such carve-out, then surely Congress could have approved a special law allowing Kennedy to go on the half-dollar coin (remember, one Congress can’t bind another).
FDR died in 1945 and was on the dime the next year, and Eisenhower died in 1969 and was on the (silverless) dollar coin two years later, so obviously the five-year limitation was not impossible to get around.
Well, rules are made to be broken. You have to remember that the country went ape after Kennedy’s assassination. The whole world in fact. JFK became a kind of Henry V of England as depicted by Shakespeare, except that Henry V was almost the real McCoy. The best verdict on the Kennedys was given by DeGaulle. He was quite taken by Jacky, but later when sometime talked about how nobly she had acted, he shrugged and said she will end on on someone’s yacht. It was a show, and now that show is over.
“X” was 25 years. The Franklin half was only made for 16 years — 48 to 63. But the Kennedy half dollar was approved by an Act of Congress, so I do not see how it was illegal.