Slain Doctor’s Son Steps Into the Fray : Abortion: David Gunn Jr. put aside his career to fight extremists, one of whom shot his father. ‘We’re dealing with murders now,’ he says. ‘They’re talking about killing human beings and calling it justifiable homicide.’

The slaying of Dr. David Gunn outside a Pensacola, Fla., women’s clinic in 1993 eliminated a prolific abortion provider. But in its aftermath, a new voice arose--that of David Gunn Jr.

“David Jr. has really become a national spokesman and a symbol,” said Ron Fitzsimmons, spokesman for the National Coalition of Abortion Providers. “He knows it, and he knows how to use that role.”

Gunn, now 23, has been featured in national advertisements for abortion rights groups and stays busy on the talk show and campus lecture circuits. Before his father’s slaying, Gunn led a low-key life as a University of Alabama-Birmingham student, a lanky fan of hard-rock music who wears his hair over his shoulders.

“I can’t just be quiet,” Gunn explained. “I really believe that I’m trying to keep someone else from being hurt.”

He was always “pro-choice,” he said, but became active in the debate because “we’re dealing with murders now. They’re talking about killing human beings and calling it justifiable homicide.”

Gunn’s talks remind listeners that the doctor’s slaying cost him and his sister a loving father, and he also talks about the violence and warns “that it could happen here.” He believes his father was the victim of a conspiracy by anti-abortion extremists, though activists deny it.

He also serves as a rallying figure for those in the abortion business. He led a procession of abortionists to the spot where his father was killed, and has served as an escort at clinics undergoing mass anti-abortion demonstrations in Little Rock, Ark., Jackson, Miss., and here.

The July 29 murders of an abortion doctor and his escort at another Pensacola, Fla., clinic were perhaps even more shocking because Gunn knew the killer--Paul Hill.

“I got to know him at the trial (when Michael Griffin was convicted of Gunn’s murder),” Gunn said. They had appeared together to argue opposing views on abortion on such shows as “Donahue,” and Gunn said it deeply unsettled him when the man he had sat beside and conversed with went out and killed.

Gunn, who earned a degree in English last year and was married in November, has temporarily dropped plans to pursue a graduate degree and will concentrate on his abortion-rights role, a role that he knows could make him a target for some anti-abortion extremist.

“I don’t worry about that,” he said. “I really . . . just don’t like to even think about that.”

He does think often about his father.

“I just miss him,” he said. “I would trade anything to have him back.”