A security camera at the house captured it all. Even the audio of the robber saying, "get against the wall. Get against the wall. This wall here. Take out your wallet. Take off your ring. I'm taking it off. You give me your purse."
The gunman took their valuables and sped away.
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Another security camera captured his car and license plate, which led police to the arrest of Bryan Sylvester last Monday, a little more than two weeks after the armed robbery.
He was also wearing an electronic monitoring device as a condition of his probation from San Joaquin County.
San Francisco Police Department Capt. Jack Hart of the Ingleside Police station told ABC7 News,"we are currently reviewing data obtained from the global positioning satellite information to determine where the suspect was, where his travels had brought him."
Police aren't saying much more, only that they're investigating the case. But sources told ABC7 News the GPS on the ankle monitor shows he was in Bernal Heights at about the time of the robbery.
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It also shows he may have been in at least two other locations in the city where other crimes were reported.
Nowadays more and more judges are ordering electronic monitoring for out of custody defendants.
They say it's a good surveillance tool, but the monitoring does not occur on real time.
San Francisco Sheriffs Department Sgt. Dwight Gunn is in charge of the department's electronic monitoring operations. "It will tell us where you're at. It won't tell us what you're doing. It is an effective monitoring tool that will deter crime. But it is not preventing crime in any way shape or form."
ABC7 News called the San Joaquin Sheriffs Department to ask the conditions under which Sylvester was put on electronic monitoring.