Law enforcement officers beat their wives or girlfriends at nearly double the rate of the rest of the population, and trying to control that is not only difficult for the victims but potentially deadly, experts say.
The trouble lies in the very nature of police work.
One of the hallmarks of a good cop is to radiate authority and control, and in the wrong hands, those characteristics can be misused, domestic violence counselors say.
When that misuse happens, it's hard to report it because the victim has to go up against a man - and it is almost always a man - and his agency, both seen by society as paragons of protection.
Even advocates for battered women are reluctant to dive into domestic violence cases involving police for fear of alienating the agencies they rely upon for help in other abuse cases. Several local advocates declined to be interviewed for this article because of that concern, although more than a dozen publicly called Thursday for Mirkarimi to step aside temporarily while the case against him is resolved.
"The biggest problem for a woman reporting that she's been abused by her police officer husband or boyfriend is that nobody believes you," said Diane Wetendorfof Chicago, who wrote a nationally used victim handbook, "Police Domestic Violence."
"If you do speak up, the police are very good at turning the accusations around," Wetendorf said. "The women get terrified, too, so the crime is very under-reported. There is a legitimate fear of retaliation."
Perhaps the most notorious case of domestic violence involving a law enforcement officer happened in 2003, when the police chief of Tacoma, Wash., shot his wife to death in front of their two children after she complained to officers that he had abused her. He then killed himself.
Several studies, according to Gandy and Wetendorf, indicate that women suffer domestic abuse in at least 40 percent of police officer families. For American women overall, the figure is 25 percent, according to the Centers for Disease Control and Prevention.
"There are a lot of good cops who go into the work for the right reasons, to help people," Wetendorf said. "But then you have these others who are more interested in the authority, in the badge and the gun."
She said officers who abuse their wives or partners often are perverting the "continuum of force" used in policing.
"They start out with command presence and voice to gain and maintain control, and if that doesn't work, they go up the scale with an increasing amount of force until they get compliance," Wetendorf said. "Unfortunately, these guys use the same technique with their wives and girlfriends. And some of them go from 0 to 60 right away."
Aside from the fear of violent retaliation, women abused by police can also have trepidation about costing their husbands their jobs and jeopardizing their own economic future, Wetendorf said. Often, they also encounter skepticism from the same law enforcement system they are complaining to.
"A big part of police culture is the code of silence," she said. "The prosecutors depend on police for their cases, the police depend on each other - it's a very insulated system."
Many of the qualities valued in on-duty police officers can make them dangerous domestic violence offenders. All abusers employ similar methods to control and abuse their intimate partners. Officers however, have skills and tactics not commonly possessed by civilians. Professional training in force, weapons, intimidation, interrogation and surveillance — along with the cultural climate — become a dangerous and potentially lethal combination in a domestic situation. Victims face the bias of law enforcement agencies and the legal system, psychological intimidation, and a high lethality risk.