Between fiscal years 2006-07 and 2010-11, Oakland police spent nearly $500,000 on a system called ShotSpotter, which , "but did not use the system, as intended, during this five-year period," according to the audit.

Only one computer was used to report ShotSpotter alerts, and no dispatcher had been posted at the computer to read alerts, it adds.

ShotSpotter also suffered from "non-use by officers for investigation," as well as the department's decision to stop system maintenance "due to budget constraints," it adds.

The OPD spent $1.2 million on an in-car video management system in fiscal 2007-08, but it was never used because it "did not work as expected" and the vendor went out of business, according to the report.

In addition, an E-Citation system that cost more than $81,000 was never used, the report adds. The product's vendor also went out of business before the department could implement it, according to the audit.