“What else did the victim’s husband say, Detective Gunn?”

“He said he fell back asleep after she called. He then woke up when she pulled into the driveway-she’s got a tricked-out Mustang with glass pipes. It makes some noise. He was lying in bed and he heard her kill the engine but then she never came inside the house. He waited a few minutes and then went out to check. He found her in the car, dead. He didn’t see anybody and didn’t see any vehicles. That was it. You can call me Kim, by the way.”

“Okay, Kim. Anybody put the husband through the box?”

“My partner. No record.”

“What about ATF?”

“We checked that, too. He owns no firearms. Neither did she.”

Bosch was holding the phone in the crook of his neck while buttoning his shirt.

“Anybody swab him?”

“You mean GSR? We figured that was a call you should make. The husband’s cooperating. We didn’t want to mess with that.”

She was right in waiting for Bosch to make the call. Conducting a gunshot residue test to determine if a person had fired a weapon had become trickier and stickier in recent years. It was in a legal gray area and choices made now by detectives would be questioned and reviewed repeatedly down the line by supervisors, reporters, prosecutors, defense lawyers, judges and juries.

The issue at hand was that such testing put the subject on clear notice that he was a suspect. Therefore, he should be treated as a suspect-advised of his constitutional rights and given the opportunity to seek legal counsel. This put a chilling effect on cooperation.

Additionally, a recent directive from the District Attorney’s Office concluded that GSR testing was an invasive evidence-gathering technique that should only come voluntarily or after a search warrant had been approved by a judge, another move that would clearly put an individual on notice that he was a suspect. So gone were the days when a detective could casually tell an individual of interest to submit to GSR testing as a routine part of an investigation. A GSR test was now an indisputable means of tagging someone as it.