Published: August 6, 1996
BY STEVE JOHNSON
Mercury News Staff Writer
EVERY MONTH or so, a male client steps behind a screen in the San Jose office of psychologist Stewart Nixon and attaches a controversial monitoring device called a penile plethysmograph to his genitals.
Then the patient stares at pictures of children in underwear or listens to tapes featuring fictional descriptions of youngsters being molested, while the gadget records changes in his level of arousal.
Although not widely known outside of therapist circles, the P-graph is used by hundreds of psychologists who rely on it to help measure and treat child molesters or others with ''deviant'' sexual tendencies. The machine also has helped generate a curious therapeutic cottage industry in sexually suggestive pictures, tapes and other ''stimulus materials'' used in connection with the tests.
The P-graph incorporates a rubber loop typically filled with mercury that fits over a patient's penis and records changes in the organ's circumference. Many people who register high on the P-graph when shown pictures of children ''don't realize they have this deviant arousal,'' Nixon said. The device's findings not only help them come to grips with their problem, he said, but it provides a way of measuring how well treatment helps them overcome their desires.
''It is valuable as a therapeutic tool,'' Nixon said. ''It tells the therapist the extent to which the individual needs help.''
Supporters like Nixon concede that the instrument shouldn't be used to determine guilt or innocence in a criminal matter, and point out that just because someone is aroused by pornographic materials doesn't mean they will necessarily act on those impulses. Nevertheless, they contend the P-graph can help spot tendencies that might prompt some people to commit deviant acts.
But other mental-health professionals and civil libertarians remain deeply skeptical of the machines. Citing studies in which the devices have failed to detect nearly one out of three known sex offenders tested, critics call the P-graphs unreliable and complain that procedures for operating them vary widely from place to place.
Moreover, they are troubled by its use in so-called aversion therapy, which involves subjecting patients to electric shocks or putrid odors while they stare at sexually suggestive pictures. The idea is to dull the patient's interest in such materials. And in such cases, psychologists use the P-graph to see how well the therapy is working.
But to critics, it all conjures up nightmarish visions of thought police and the futuristic images of ''A Clockwork Orange.'' And even some of those who use the P-graph fear that in the wrong hands it could cause harm.
''We have serious doubts about it,'' said Ted McIlvenna, president of the Institute for Advanced Study of Human Sexuality in San Francisco, which has a P-graph and offers training on its use to others. Although the device can be useful for uncovering some information about people, he conceded, ''it reminds me a little bit of new technology for an inquisition.''
Last year, revelations that the test was being done on people in British jails prompted denunciations from prison-reform advocates who called the procedure ''degrading.'' In Old Town, Maine, officials three years ago had to pay nearly $1 million to settle a lawsuit by a policeman who claimed he was threatened with firing after refusing to take a P-graph.
And in 1992, disclosures that the P-graph was being used by publicly financed agencies in Arizona and Texas on boys as young as 10 years old also sparked outrage. As a result, a program for sex offenders in Phoenix was shut down and the U.S. Food and Drug Administration cited a Nebraska P-graph manufacturer for selling the device without federal approval.
Because of such problems, some manufacturers say sales of P-graphs have been slow in the past couple of years. Nevertheless, David Davids, who owns Medical Monitoring Systems in New Jersey, one of the leading P-graph firms, said business has picked up again in recent months.
''We're just getting a lot more calls now, mainly from corrections departments'' or people affiliated with them. Because of public concern about sex offenders, he added, ''the pressure is on the politicians to get something done.''
Sex offenders at Atascadero State Hospital have been tested by the P-graph and a spokeswoman with the state Corrections Department said that agency contracts with a Shasta County outfit that administers it. Moreover, Robert Card, president of Behavioral Technology Inc. in Salt Lake City, said his company has sold P-graphs to other jail officials and consultants in California, though he declined to name them.
In Santa Clara County, however, officials who deal with sex offenders say no public agencies use the device. And among the county's psychologists, according to deputy adult probation officer Jim Manganello, Nixon ''is the only guy I know who's using it.''
Nixon stresses that he only uses the machine along with polygraph tests or other data obtained through more traditional psychological techniques. And on the occasions when he has been asked to evaluate people in criminal sexual cases, Nixon said, the defense attorneys who hire him and other court officials usually don't know or seem to care when he includes P-graph data in his reports or testimony.
Nevertheless, he acknowledges that ''there is some degree of controversy'' about the gadget.
Some psychologists shy away from the machine because of negative publicity over the graphic pictures and tapes often used in the tests to elicit sexual arousal.
The Association for the Treatment of Sexual Abusers advises P-graph operators to use a variety of ''appropriate and deviant'' themes, which may include pictures of sex acts. ''Typical audio tapes include fondling, consenting/nonforceful intercourse, coercive sex, rape, and assault with both children and adults of both sexes.''
While laws in California and other states permit some use of sexually explicit materials for scientific or educational purposes, psychologists say obtaining it isn't always easy. Some prowl adult book stores or tap police sources for the stuff. Others buy it from a number of entrepreneurs who have jumped into the market to serve P-graph testers.
Because of the variety of sources supplying it, the materials used vary considerably from one therapist to another, which critics say can bias the P-graph's data.
Nixon said he shows patients pictures of children in underwear or in bathing suits, while other testers use pictures of children in the nude. And while Nixon uses relatively tame audio tapes prepared by Atascadero hospital researchers, others have used video tapes that are so raunchy they've been denounced as pornographic.
Moreover, sex offenders often have different preferences. So if a tester doesn't happen to have the kinds of materials that turn an offender on, critics add, the P-graph may be fooled about that person's sexual tendencies.
Over the years, people dealing with sex offenders have experimented with all sorts of gadgets to measure deviancy -- from penile temperature gauges to ''pupillographs,'' which record changes in eye movement. Last year, an Atlanta firm called Abel Screening Inc., came out with a computer software program that measures it based on how long a person viewing pictures of children and adults lingers over certain images.
So far, two California therapists have bought Abel's software, which costs $3,000, plus an additional $75 to process each test. Nixon is thinking about getting it, too. But he said he's waiting to see more research on the program's effectiveness.
For the foreseeable future, he and a lot of other therapists are likely to stick with the P-graph, experts say. Ever since Czechoslovakian officials reportedly developed it in the 1960s to monitor the sexual orientation of draftees, P-graphs have remained the instrument of choice for detecting sexual deviancy, even though the devices cost at least $8,000.
''It's been misused in court; it's been misused by therapists,'' said Steve Jensen, a board member with the Association for the Treatment of Sexual Abusers who uses the device at his Center for Behavioral Intervention in Beaverton, Ore.
But, he added, ''it is effective at measuring arousal. So until somebody replaces it, therapists who are competent are going to continue to use it.''
