The nephew of assassinated president John F Kennedy claimed the inquiry into him amounted to "the weaponisation of our government against political opponents".
The 70 year old told a rally at the weekend: "I received a letter from the National Marine Fisheries Institute saying that they were investigating me for collecting a whale specimen 20 years ago."
The Centre for Biological Diversity Action Fund contacted the authorities. Director Brett Hartl said: "RFK Jr cutting off the head of a dead whale was both bizarre and illegal." In 2012 Kennedy's daughter, Kathleen, told a magazine that when she was a child her father used a chainsaw on a dead whale.
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