At age 11 in 1922, he was arrested for truancy. His troubled childhood and adolescence were marked by juvenile delinquency with time being spent in foster homes. While he was growing up, his parents were often violent towards each other and frequently separated Ruby's mother was eventually committed to a mental hospital. Ruby was the fifth of his parents' 10 surviving children.

Ruby was born Jacob Leon Rubenstein on or around March 25 or April 25, 1911, in the Maxwell Street area of Chicago, the son of Joseph Rubenstein and Fannie Turek Rutkowski (or Rokowsky), both Polish-born Orthodox Jews from Sokołów. These findings were challenged by various critics who suggested that Ruby was involved with major figures in organized crime and that he was acting as part of an overall plot surrounding the assassination of Kennedy. In September 1964, the Warren Commission concluded that Ruby acted alone in killing Oswald, shooting him on impulse and out of grief over Kennedy's assassination. Ruby's conviction was later appealed, and he was to be granted a new trial however, he became ill in prison and died of a pulmonary embolism from lung cancer on January 3, 1967.

A Dallas jury found Ruby guilty of murdering Oswald and sentenced him to death. Jack Leon Ruby (born Jacob Leon Rubenstein April 25, 1911 – January 3, 1967) was an American nightclub owner and alleged associate of the Chicago Outfit who murdered Lee Harvey Oswald on November 24, 1963, two days after Oswald was accused of the assassination of President John F. Algeria, Angola, Argentina, Australia, Bahrain, Benin, Bermuda, Bolivia, Botswana, Brazil, Brunei Darussalam, Burkina Faso, Burundi, Cambodia, Cameroon, Canada, Cape Verde Islands, Central African Republic, Chad, Chile, Colombia, Comoros, Côte d'Ivoire (Ivory Coast), Democratic Republic of the Congo, Djibouti, Ecuador, Egypt, Equatorial Guinea, Eritrea, Ethiopia, Falkland Islands (Islas Malvinas), Gabon Republic, Gambia, Germany, Ghana, Greenland, Guinea, Guinea-Bissau, Guyana, Hong Kong, Indonesia, Iraq, Israel, Japan, Jordan, Kenya, Kuwait, Laos, Lebanon, Lesotho, Liberia, Macau, Madagascar, Malawi, Malaysia, Mali, Mauritania, Mauritius, Mayotte, Mexico, Morocco, Mozambique, Namibia, New Zealand, Niger, Nigeria, Oman, Paraguay, Peru, Philippines, Puerto Rico, Qatar, Republic of the Congo, Rwanda, Saint Helena, Saint Pierre and Miquelon, Saudi Arabia, Senegal, Seychelles, Sierra Leone, Singapore, Somalia, South Africa, Suriname, Swaziland, Taiwan, Tanzania, Thailand, Togo, Tunisia, Turkey, Uganda, United Arab Emirates, United Kingdom, Vietnam, Virgin Islands (U.S.41★7′29″N 87☄9′37″W / 41.958110°N 87.826853°W / 41.958110 -87.826853

Mad Dog House by Mark Rubinstein