Perhaps the biggest surprise in The Atlanta Journal-Constitution's Doctors & Sex Abuse investigation was the frequency with which medical regulators kept predators in practice. Perhaps more surprising was this: Across the nation, regulators thought a simple restriction could ensure patient safety — requiring a chaperone to be present during examinations.

Some doctors continue molesting patients even in a chaperone's presence. Some even get a thrill from misbehaving under such close scrutiny.

Related: Read the AJC's Doctors & Sex Abuse project.

Medical officials in Australia recently determined that chaperones are often ineffective, and they will no longer ask them to supervise doctors under investigation for sexual misconduct. Instead, regulators will either suspend accused doctors or impose restrictions on the gender of patients they can see.

The Medical Board of Australia and the Australian Health Practitioner Regulation Agency based their decision on a study that followed news reports about a doctor who allegedly molested three patients while under a chaperone's supervision. According to the Sydney Morning Herald, the doctor, Andrew Churchyard, molested one of the patients behind a curtain while the chaperone was in the room.

Churchyard, a neurologist, was accused of sexual misconduct involving several dozen patients over 13 years. He committed suicide last summer before going to court on sexual assault charges.

The Australian study pointed out several problems: chaperones may lack training, many work for the physician they are supposed to oversee, and they may have other duties that distract them during examinations. In the United States, the AJC found, most doctors under a chaperone's supervision were not required to explain the third person's presence in the exam room. (In some states, such as Georgia, doctors are supposed to bring in a third person for intimate exams, so that person's presence doesn't necessarily mean the physician has been disciplined for misconduct.)

An AJC story last year used the example of Dr. Alfredo Garcia to demonstrate the shortcomings of relying on chaperones.

In 1989, New Jersey regulators ordered Garcia to have a chaperone when he examined women patients. But beginning in 2000, he repeatedly performed what the State Board of Medical Examiners described as inappropriate exams when a chaperone was not present. In 2004, after Garcia served a 150-day suspension, the board ordered him to treat female patients only with "the presence of an authorized third party." His misconduct continued, and in 2012, he pleaded guilty to sexual misconduct charges and was sentenced to seven years in a state treatment facility.

A news report said Garcia sexually abused patients during exams supervised by nurses by disguising his actions as medical procedures. A prosecutor was quoted as saying Garcia told a psychologist that "what excited him was the fact that he was ... getting away with it."

In a report on the Australian study, Professor Ron Paterson of the University of Auckland suggested other countries would also stop relying on chaperones to prevent sexual misconduct.

“Predatory practitioners who have come to view patients as sexual objects may not be deterred by a safety mechanism that still leaves the practitioner in control,” Paterson said.

Staff writer Ariel Hart contributed to this article.