LITTLE ROCK (AP) - Tenmen were seated as jurors in the first degree murder trial of James Dean Walker, 22. of Reno, Nev., in circuit court here Tuesday.He is charged with shooting North Little Rock Policeman Jerrell P. Vaughan in a gun-fight April 16. 1963.Vaughan had stoppeo a car outside North Little Rock after Walker and another man had been involved in a fight in a Little Rock club.Prosecutor John Jemigan qualified the jurors for the death penalty.Walker pleaded innocent and innocent by reason of insanity at his arraignment. Defense Attorney Harold Hall said thepleas would be maintained.Judge William J. Kirby imposed. tight security on the courtroom, with state and city officers stationed at entrances to search persons entering the court room.The security precautions were taken because on April 22, 1963, three 'persons kidnaped, an Arkansas Baptist. Hospital employe and tried to learn from her the number of Walker's room. The defendant was in the hospital recuperating from bul-