The JFK assassination was committed by Lee Harvey Oswald.
After Oswald attempted to defect to the Soviet Union, who showed no interest in him, he tried to return to the US. Oswald attempted to assassinate retired Major General Edwin Walker, and displayed several instances of extremist actions against those who he disagreed with politically.
After obtaining a job at the Texas Schoolbook Depository, Oswald shot and killed John F. Kennedy while Kennedy visited Dallas. The police locked down the building, but Oswald slipped out shortly before this occurred. After returning home and changing clothes, Oswald stepped onto the sidewalk and was stopped by a policeman.
Oswald shot the officer 4 times and fled, hiding in a theater, where he was soon charged with killing the officer, and by the end of the day charged with killing the president.
There are no contradictions, and people who believe highly embellished alternative stories have a desire to do so.
About 40 people who could speak out about the crime died myseriously, his brother was also killed, Martin Luther King was killed and Marylin Monroe which had an affair and maybe had secret informaions died also pretty young and I don´t think that individuals were able to this monstrous crime.