Fifty years after shots rang out in Dealey Plaza, killing a larger-than-life figure and abruptly ushering in what one historian has called “the decade of shocks” – from Dallas to Watergate – the federal agency that stood at the center of seemingly all the intrigues and conspiracy theories of that shadowy era is still holding onto an estimated 1,100 documents relating to the assassination of President John F. Kennedy. [...] One official who has drawn particular scrutiny by researchers is the late George Joannides, an undercover CIA officer who worked in Miami and New Orleans in the early 1960s. Researchers...