When a man raised his shirt and pulled down his pants to a woman near downtown Palo Alto on Jan. 31, his act was perhaps shocking. But psychology and criminology experts say it doesn't necessarily mean the man, if he did do the crime, will commit violent sexual crimes in the future.

Recent indecent exposures in the Palo Alto area have concerned residents and law-enforcement officials alike. Police began making the incidents public in early January, when the flurry of flashing began.

In Palo Alto, two men were recently arrested for the crime, one on Jan. 20 near Juana Briones Park and the second on Jan. 31. Two other incidents of indecent exposure occurred on Jan. 8 and 10, but no one has been arrested.

The first offense is considered a misdemeanor, but each subsequent conviction is a felony, Palo Alto police spokesman Lt. Zach Perron said. It's also a felony to enter a residence without consent and expose oneself. The perpetrator of a felony can be sentenced to state prison.

California law requires convicted persons to register as sex offenders.

Indecent exposure is the most prevalent sexual crime, accounting for one third of all such reported crimes, with the majority committed by men, according to the Journal of Forensic Psychiatry.

Incidents seem to come in waves, according to Toni DuPont-Morales, a specialist in victimology at California State University at Fresno Department of Criminology. Some occur after other incidents are publicized, especially if the perpetrator is not caught.

"Think of it from their perspective. This is exciting, and the chances of getting away with it are really good," she said, noting the brief nature of flashing and the probability that victims won't report the incidents to police.

So what danger does a flasher pose? Researchers say there are a host of factors that predict the potential for more egregious crimes, including whether the offender corners or makes contact with the victim.

Perron said flashers gain satisfaction from their action, but other than that, it is difficult to generalize about their motives or future behavior.

"Every suspect is different. In some cases, indecent exposure may indeed be a precursor for someone who may go on to commit a more serious crime. In other cases, the indecent-exposure event is the worst and/or only crime that person will commit," he said in an email.

DuPont-Morales, who has worked with offenders and victims, said extreme immaturity and "really liking that fear or surprise of the victims" characterize the psychology of offenders.

Some experts argue that perpetrators have issues with control. DuPont-Morales agreed. Control and eliciting a reaction from the victim do seem to be part of the drive, she said. Some offenders seek out victims they think will provide the desired reaction.

And timing also plays a role in offenders' thinking. A study in the United Kingdom found that flashers committed their crimes in the early morning when people were rushing to work and didn't have time to report the behavior. Crowded downtown areas were also favored, as were university libraries and small hallways, where there were opportunities for brief contact, DuPont-Morales said.

Many people who flash choose to deviate in other sexual ways, and those who rape are likely to have tried other sexual behaviors, DuPont-Morales said.

But as alarming as indecent exposure might be, not all people who expose themselves go on to commit more serious crimes. An indication of the likelihood of violence is the person's willingness to get close to a victim, she said.

Even without violence, any time a flasher chooses a child as his victim, it is dangerous, DuPont-Morales said.

One such incident occurred in Menlo Park on Feb. 1, and the offender has not been arrested.

A man in a van approached an 11-year-old girl at around 7:45 a.m. and exposed himself near Ivy Drive and Windermere Avenue. He threatened to harm her if she told anyone about the incident, Menlo Park police said.

DuPont-Morales said this kind of case is disturbing.

"He had the capacity to grab. That is far more dangerous. ... He had the capacity to escalate very rapidly," she said.

A victim may be able to influence whether the incident might turn violent, however. Victims should not strike the flasher or swear at him -- and it is not advisable to laugh, she said.

The best protection?

"The victim can protect themselves by moving on," she said.

Some flashing victims do feel psychologically harmed and may need counseling, DuPont-Morales said. While some people just laugh off the experience, others have considerable anxiety.

Short-term counseling is usually adequate for most victims, but in the case of of a child, such as in the Menlo Park incident, "that little girl needs more than that," she said.

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