No, if you're referring to Justin Bieber the singer. He wasn't born until 1994 so its not possible that he could have been assassinated in 1959.
Justin Boyle was born in 1959.
Justin Colfax Morgan died in 1959.
Justin J. McCarthy died in 1959.
Justin Catanoso was born on 1959-11-05.
Michael Kolnberger was born in 1959.
Michael Bavaro was born in 1959.
Michael Josephs was born in 1959.
Michael Balboni was born in 1959.
Michael Greif was born in 1959.
Michael Colbert died in 1959.
Michael Wachtler was born in 1959.
Michael Whitley died in 1959.