Gregory Scruggs used a revolver, Darryl Headbird a shotgun, Justin Trammell a crossbow. They are among scores of American adolescents convicted every year of killing their fathers.

This week, 12- and 13-year-old brothers in northern Florida were charged with the same crime _ again raising questions about what could provoke an act that seems so taboo.

The immediate motive in such cases can appear petty or selfish, but experts say the slaying often follows prolonged abuse or a severe family breakdown.

Authorities frequently consider more lenient sentencing and rehabilitation options for youths who kill their parents than for those convicted of slayings outside their family.

``Maybe some killed for money, or because they couldn't use the family car, but the overwhelming majority are responding to abuse and extremely dysfunctional families,'' said Paul Mones, a Portland, Ore., lawyer who has studied many cases of parricide.

Authorities in Florida have yet to suggest a motive that might have prompted Derek King, 13, and Alex King, 12, to kill their father. The body of 40-year-year-old Terry Lee King _ whose head had been battered _ was found Monday when firefighters responded to a blaze at the family home outside Pensacola.

Motives have been clear in some other recent cases. Scruggs, 13, told the judge who convicted him in Cleveland last week that he shot his father in self-defense because of years of abuse that included beatings with hangers and mop handles.

Headbird, then 14, gunned down his father on an Indian reservation in Minnesota last May because the father was discouraging a romance, according to authorities. Trammell, now 17, killed his father with a crossbow two years ago in Arkansas because of worries that his plan to run away would be thwarted.

Mones said there are 200 to 300 parricides _ the killing of a parent by a child _ in America each year, with about half committed by youths under 18. The most recent FBI statistics, for 1998, showed about 100 killings of parents by children under 18.

About 70 percent of the parricide cases involve boys who kill their fathers in response to some type of abuse, Mones said.

``Most of these kids don't have the same profile as kids who kill strangers,'' he said. ``They tend to have average to above-average intelligence. They're polite, they obey adults. They generally don't have a history of acting violently at all.''

Often, trials in these cases result in conviction on a charge less than first-degree murder. Headbird, for example, was convicted of second-degree murder, while Conan Pope, a Nevada teen who killed his father in a dispute over dirty dishes, pleaded guilty in May to voluntary manslaughter and could be out of prison in four years.

``The trend is to treat these kids as juveniles, and to give them some sort of treatment even if they are transferred to adult court,'' Mones said. ``The research literature shows these kids are extremely well-suited to rehabilitation.''

Pope had already received extensive counseling when he was sentenced, tearfully telling a judge he wished his father was still alive. ``But my family was not healthy,'' he said. ``It was filled with violence, fear, guns, drugs and abuse.''

Kathleen Heide, a criminology professor at the University of South Florida and author of the book ``Why Kids Kill Parents,'' says there are three basic types of children who commit parricide:

_Those acting out of desperation or terror after experiencing abuse or seeing others in their family abused. This is by far the biggest category, Heide says.

_Those who are dangerously anti-social, who have been in trouble with the law before and see their parents as an obstacle to their ambitions.

_Those who kill because of unchecked mental illness.

Adam Weisman, who teaches psychology at Pepperdine University, said authorities should be open-minded in judging each parricide case.

``It's easy to look at the parents and say it's all their fault, but you have to look at the dynamics,'' he said. ``Is there prior juvenile delinquent experience? Has there been some knocking around of the parents, and the parents taking it because the kids have gotten too big for their britches?''

Friends of the Kings in Florida said Friday that Terry King was strict with his sons, but expressed surprise at the deadly violence.

The boys were being held in a juvenile detention facility. Prosecutors plan to ask a grand jury to indict them as adults on charges that could range from first-degree murder to manslaughter.

Terry King and the boys' mother, Janet Lyttle, now living in Kentucky, never married and she has had little involvement with them since the couple broke up in 1995, friends said.