Shortly after a Florida antiabortion group launched its campaign against obstetrician-gynecologist Frank Snydle, his 80-year-old mother received a 3 a.m. telephone call.

"Whoever it was told her that he was a trooper with the Florida Highway Patrol and that I'd been killed in a car accident," said Snydle. "My mother has a heart condition. By the time she found me several hours later, she was hysterical."

That, said Snydle, is one of many tactics antiabortion groups have used in a concerted campaign to pressure him to stop performing abortions. Snydle, 47, who has performed abortions at clinics in Melbourne and Orlando, Fla., has been followed repeatedly. His car windows have been smashed. His home and private medical office have been picketed.

"Wanted" posters featuring a $1,000 reward for information leading to his arrest or the revocation of his medical license have been circulated widely in central Florida. The posters also listed his mother's address and phone number and the license plate numbers for two ex-girlfriends' cars. The children of one of the former girlfriends, he said, were taunted by protesters as they waited for a school bus.

Although statistics are elusive, abortion rights advocates and physicians' groups, including the American Medical Association, say increasing numbers of doctors around the country are the targets of aggressive campaigns to stop them from performing abortions. The site of the protests has shifted from the clinics where most of the nation's 1.6 million abortions are performed annually to the homes of doctors who perform them.

In Melbourne, two doctors stopped working at an abortion clinic last month because they said they feared for their safety. In Dallas, at least three physicians in the past year have stopped performing abortions after they were pressured by an antiabortion group.

Abortion rights advocates say the campaigns are illegal efforts to harass and intimidate doctors. Antiabortion activists say the campaigns are legally protected protests; their purpose is to educate and expose doctors and, ultimately, to make them stop performing the procedure.

Snydle "would certainly describe these incidents with a totally different attitude than we would," said Bruce Cadle, field director of Operation Rescue National, who spearheaded the "No Place To Hide" campaign against Snydle. "He knows we're not violent."

Cadle said he had no involvement in and does not condone the telephone call to Snydle's mother, any destruction of property or the targeting of children. The other activities, he said, are legal and effective tactics.

A Sharp Rise in Violence

Last month's murder of obstetrician David Gunn, who was shot in the back three times by an antiabortion protester as he walked into a Pensacola, Fla., abortion clinic, has focused new attention on these campaigns. Abortion rights advocates say they account for a sharp increase in the violence against doctors and abortion clinics recorded since 1991.

In 1990, according to statistics compiled by the National Abortion Federation in conjunction with local, state and federal law enforcement agencies, about 100 violent abortion-related incidents, including bombings, arson and death threats, were reported to police. By 1992 the number was 667. Federation executive director Barbara Radford said these numbers are low, because many health care workers, particularly physicians, have been reluctant to report harassment or other crimes, fearing they may provoke further violence.

"In all too many cases local law enforcement is unwilling to do their job to protect physicians and their families," said Rep. Nita M. Lowey (D-N.Y.), chairwoman of the Women's Caucus Pro-Choice Task Force. Lowey, who has introduced a bill linking the receipt of federal community development funds to the enforcement of local harassment and stalking laws, said, "I think there are many people who have mixed views on this issue . . . abortion has been marginalized, it is seen as a woman's problem" or as a political matter.

The Clinton administration's support of abortion rights, combined with the reaction to Gunn's murder, has given the issue renewed urgency. Last week the House Judiciary subcommittee on crime and criminal justice held a hearing on violence against abortion providers. At that hearing subcommittee Chairman Charles E. Schumer (D-N.Y.) released a letter from Attorney General Janet Reno, who said she favors new federal legislation to protect doctors and other workers from harassment away from clinics.

Not all abortion foes support the campaigns against doctors, which have been organized and executed by a variety of groups, including Operation Rescue and its affiliates, Missionaries to the Preborn, Rescue America, the Pro-Life Action Network, the Pro-Life Action League and the Lambs of Christ.

The National Conference of Catholic Bishops, one of the few antiabortion groups to strongly condemn Gunn's murder, does not support activities that single out doctors or their families. Nor, said spokeswoman Helen Alvare, does it condone violence of any kind, including "verbal harassment."

"We are opposed to following clinic employees or their children" or to any activity that is not "explicitly peaceful public witness," Alvare said. Such efforts "may seek a good end -- such as stopping abortion -- but you can't use a bad means to get there."

Randall A. Terry, the founder of Operation Rescue and the nation's best-known antiabortion leader, denied that the campaigns are in any way responsible for Gunn's death or other abortion-related violence.

"We are not responsible for creating this climate {of violence}," Terry said in an interview. "They are the mass murderers." Gunn's murder, he said, was "one isolated, abnormal act" that is being exploited by abortion rights groups and the national media "who are at the beck and call of the child-killers."

Terry, who vowed last year at a rally in the District to "do everything we can to torment these people {doctors} . . . to expose them for the vile, blood-sucking hyenas that they are," told the congressional panel that he and his followers were using "our First Amendment privileges to expose them, to humiliate them, to disgrace them, which is our right."

During a tense exchange with Schumer, Terry said he thought there was a "Grand Canyon of a difference" between illegally harassing a physician and legally exposing a practice one believes is harmful.

Terry repeatedly has said that the goal of such campaigns is to make targeted doctors "a liability to everyone they encounter," subjecting them to pressure from their patients, their employees, other doctors on whom they depend for referrals, their neighbors, members of the same church, synagogue or club, their landlords and their families. He has suggested that abortion opponents follow a doctor's wife to the hairdresser and stand outside with picket signs that say, "This hairdo is paid for by blood money."

"The doctor is the weak link," Terry said in the interview. As evidence, he cited findings that abortion is unavailable in 83 percent of U.S. counties and that a dwindling number of obstetrics-gynecology residency programs offer training in abortion.

Although Terry is widely believed to be the architect of this strategy, its originator is Joseph M. Scheidler, executive director of the Chicago-based Pro-Life Action League and a key strategist of the antiabortion movement. Scheidler, who is Terry's mentor, has been active in antiabortion activities since 1973 and is the author of a 1985 book entitled "Closed: 99 Ways To Stop Abortion."

In the book, he details specific actions aimed at doctors and their families, which have been widely used in campaigns by various groups. They include residential picketing, covert surveillance and intelligence gathering.

Scheidler said in an interview that campaigns against doctors are more effective than clinic blockades, which require a steady supply of protesters willing to risk arrest.

"We haven't been successful in getting the Human Life Amendment passed or in getting Roe overturned," Scheidler said in a reference to Roe v. Wade, the 1973 Supreme Court decision legalizing abortion. "When you get doctors out, you can have all the laws on the books you want and it doesn't mean a thing."

To be successful, said Scheidler, whose brother is a doctor, campaigns require information. "We get people in the hospital who know the doctor's schedule and can get a printout, which gives you a lot of stuff: the name, address and phone number of the woman, the gestational age of the baby, how many abortions the doctor performs a week. That's how we found out about Gunn."

Spouse as 'Part of the Team'

Residential picketing, Scheidler said, is "very effective because it brings their trade right into their families and their neighborhoods" and often creates a rift among neighbors. Targeting spouses is acceptable, he said, "if you've tried to deal with the wife and she's for {abortion}, well, she's part of the team." Scheidler said he opposes "going after kids." But he said he believes it is permissible to try to talk with adolescents about what their parents do.

Abortion rights advocates said they have long been frustrated by the failure of some police departments, prosecutors and judges to vigorously pursue complaints of harassment filed by doctors and other clinic staff members.

"Abortion providers have been told to use the legal system and we have, to no avail," Susan Hill, executive director of the National Women's Health Network of Raleigh, N.C., told the congressional panel. Hill's firm owns and operates eight abortion clinics in the South and Midwest, including several at which Gunn worked. "We have obtained over 1,000 arrests. We have spent over $500,000 in legal fees. We have been awarded damages and attorneys fees of over $100,000. We have collected zero." In many cities, she said, protesters who are arrested find that the charges are dropped at trial or else they are given a $25 fine.

"We are attacked by a group of people who have been taught how to be judgment-proof and how to beat the system," she said.

Scheidler, who is finishing a sequel to his book that will contain methods of circumventing recent laws that outlaw residential picketing, agreed. "I've got eight major lawsuits going against me," he said. "Why do they keep suing us? Because we're effective."

Among the cases pending against Scheidler is a lawsuit originally filed in federal court in l986 by the National Organization for Women and the National Women's Health Network that accuses him, Terry and others of racketeering and extortion, and alleges that they are engaged in an illegal conspiracy to shut down abortion clinics. That case has been appealed to the Supreme Court after two lower courts rejected NOW's claim. The court has asked the solicitor general to file a brief about whether federal racketeering law applies in the case. That brief has not yet been filed.

Scheidler predicted that tougher enforcement of existing stalking statutes or new federal legislation would be ineffective. "They're trying to call what we do stalking, but these laws are new and kind of vague. If you have a whole bunch of people doing it, is that stalking? We'll have to deal with that as we see what happens. We're going to go right ahead with the things we're doing."

Questions about the line between illegal harassment and legitimate dissent have troubled Reuben Greenberg, chief of police in Charleston, S.C., for more than a year. Since December 1991, his department has received nearly a dozen complaints filed by Lorraine Maguire, director of the Charleston Women's Medical Clinic. Maguire says she has been stalked, harassed and threatened repeatedly by Cathy Ann Rider, a leader of the South Carolina Missionaries to the Unborn.

"I am very much disturbed by some of the tactics of the persons associated with the antiabortion movement," Greenberg said. "It's a very sophisticated form of harassment, not something that the average patrolman can say, 'I'm going to charge them with such and such.' "

A perfect example, said Greenberg, is an unsigned flier that was distributed last year in Charleston's poorest neighborhoods. The flier listed the name, address and closing time of the clinic and said, "The killers accept only cash! They kill about 60 babies each week. That is $16,500 of CASH taken to the bank each week. That means that an average of $5,500 is waiting there each day of business in cash before closing hours."

Greenberg, who called the leaflet "shocking . . . an invitation to rob the place," said he consulted the city attorney about possible legal action. He said he was told there were no legal grounds for prosecution.

"We never found out who did it or whether it was endorsed by an organization," Greenberg said. He said he believed it was drafted with legal help, "constructed in exactly the right way, because it was highly questionable whether anyone could ever be charged" even if the clinic was robbed.

Arrest on Stalking Charge

On March 31, Charleston police arrested Rider on a charge of stalking Maguire, a misdemeanor that carries a maximum penalty of a year in jail and a $1,000 fine. According to the arrest warrant, Rider on March 22 made "strong references to the murder of Dr. Gunn" when she advised Maguire to get a bulletproof vest and told her that she would need federal marshals, not the clinic's lone security guard, to protect her. In addition, the warrant states, Rider "has, among other things . . . informed McGuire {sic} that she knows the layout of furniture in the McGuire home; has referred to Ms. McGuire's daughter and encouraged others to 'rip her arms off' so that Ms. McGuire would know how aborted fetuses feel."

Rider is free on her own recognizance. A restraining order requires her to stay 500 feet away from Maguire, her family and the clinic and to refrain from disseminating personal information about Maguire or her family.

Rider's attorneys declined comment. Keith Tucci, executive director of Operation Rescue National, which is based in nearby Summerville, S.C., issued a statement saying that she was the victim of "a witch hunt."

In an interview before her arrest, Rider denied that she harassed or threatened Maguire or her daughter. She said she was "inciting people to know the truth about Lorraine Maguire and her abortuary."

"If Lorraine Maguire feels like she's being harassed," she said, "what does it feel like to have your head being ripped off by a vacuum machine?"

"Is this woman alive today? Is her daughter alive today? I have no intention of hurting these people," she said. "I want Lorraine Maguire to fall on her face before God and repent. Everything I do is to provoke her repentance."