Prosecutors hoped to present evidence at a December 20th detention hearing for Adrian Duane Johnson that could have kept the theft suspect locked up until his next hearing in January, but their witness didn’t show up to court.

That left the DC magistrate judge no choice but to order Johnson released that afternoon, with the provision he come back the next day to be fitted for a GPS monitoring device. Johnson never returned for the device.

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On Wednesday, with Johnson facing first-degree murder charges in the slaying of Bloomingdale yoga teacher Tricia McCauley, two law enforcement sources told WUSA9 the no-show witness at the detention hearing was the officer who arrested him for the theft charge in the first place.

According to one source, prosecutors asked the officer to appear in court, but did so less than 24 hours before the hearing. The source says the officer told the prosecuting attorneys he could not attend the hearing and offered the name of another office in his place.

Asked on Wednesday evening why the officer did not appear in court, and to clarify department policy for officers attending court in cases they are involved in, MPD spokesman Dustin Sternbeck responded with an emailed statement.

“We are looking into the matter and will get back to you as soon as we can with a response,” the statement reads. “Also, officers not being present at preliminary hearings or detention hearings is not uncommon, but we will look into this specific case further.”

A statement from DC Police Union spokesman Gregg Pemberton provided little additional information.

“There are a number of different agencies that are responsible for providing testimony in a detention hearing at DC Superior Court: Pretrial Services Agency, Court Services and Offender Supervision Agency, as well as MPD and other police agencies,” Pemberton wrote.

“It is unclear at this time if an MPD officer was scheduled to appear and/or if he or she was properly notified of the hearing date and time,” he continued. “There are a myriad of reasons that misdemeanor cases are dismissed by the USAO at the preliminary phases of prosecution.”

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Johnson’s theft case was not dismissed. The judge ordered him to return to the Pretrial Services Agency the next day to be fitted for a GPS monitoring device to wear until his next hearing in January. As a defendant in a non-violent misdemeanor case, his absence the next day appeared to raise no alarm bells.

“There are seventeen hundred offenders just on the post-side on GPS. There are thousands more under pre-trial services. It’s not like that’s an incredibly special condition in DC,” explained Aaron Davis of the Washington Post – author of an in-depth investigation into DC’s Court Services and Offenders Supervision Agency (CSOSA), of which Pretrial Services is a part.

“There are thousands in this pool and so It might take days—not uncommon to take weeks—to then have him picked up for that kind of a violation,” Davis said.

A spokesperson for CSOSA declined to answer any questions about the Johnson case, or the agency’s policies on GPS monitors.

DC’s status as neither a city, county or state has created a patchwork of law enforcement agencies and court systems unique in the country, Davis explained. Officers of the court have comparatively little power to get warrants or make arrests in a timely fashion for probation or other violations by defendants.

Many law enforcement experts agree that GPS monitoring devices do not serve as strong deterrents against crime.

In this case, that lack of monitoring appears to be one of several missed opportunities to prevent a tragedy.