The Los Angeles County Sheriff's Department acknowledged this week that Compton residents were not notified of an airborne video-surveillance program that was tested in 2012.
"No notification to the residents was made because this system was being tested in a city where cameras were already deployed and the system was only being evaluated," the department said in a statement released Tuesday.
Officials said the department decided the program was not useful and dropped it after the test period.
Under the nine-day trial program in January 2012, a video camera was mounted on a small plane that was deployed for six-hour periods during the day, the department said.
The plane, which flew out of Long Beach Airport, was operated by a private company that provides airborne surveillance technology.
The department said Compton was chosen, in part, because it features 10 square miles of flat topography. But the resolution of the video footage was not sufficient to allow authorities to identify people who might have been involved in breaking the law, according to the department.
"The images from the surveillance footage weren't clear enough," said Nicole Nishida, a department spokeswoman.
This month, the Bay-Area based Center for Investigative Reporting and the KQED public radio station reported on airborne surveillance systems used by law enforcement, including the program used in Compton.
The report noted people in Compton had heard little about the surveillance program.
The department said 20 surveillance cameras are deployed in city parks and monitored to help keep the community safe.