California finally releases wiretap dataset

In 2016, California investigators used state wiretapping laws 563 times to capture 7.8 million communications from 181,000 people, and only 19% of these communications were incriminating.  The year’s wiretaps cost nearly $30 million.

We know this, and much more, now that the California Department of Justice (CADOJ) for the first time has released to EFF the dataset underlying its annual wiretap report to the state legislature.

The yearly “Electronic Interceptions Report” includes county-by-county granular data on wiretaps on landlines, cell phones, computers, pagers1, and other devices.  Each interception is accompanied by information on the number of communications captured and the number of people those communications involved, as well as what percentage of the messages were incriminating. The report also discloses the criminal justice outcomes of the wiretaps (e.g. drugs seized, arrests made) and the costs to the public for running each surveillance operation.

Under California’s sunshine law, government agencies must provide public records to requesters in whatever electronic format they may exist. And yet, for the last three years, CADOJ officials resisted releasing the data in a machine-readable format. In fact, in 2015, CADOJ initially attempted to only release the “locked” version of a PDF of the report until EFF publicly called out the agency for ignoring these provisions of the California Public Records Act.

EFF sought the dataset because the formatting of the paper version of the report was extremely difficult to scrape or export in a way that would result in reliable and accurate data. Tables in the reports have sometimes spanned more than 70 pages.

This year, EFF has scored a major victory for open data: in response to our latest request, CADOJ has released not only an unlocked PDF, but a spreadsheet containing all the data.

What’s especially interesting about the data is that it includes data not previously disclosed in the formal report, including information on when wiretaps targeted multiple locations, devices, and websites, such as Facebook. At the same time, the data does not include some information included in the official report, such as the narrative summary of the outcome of each wiretap.

Some of the highlights contained in the data.

  • Wiretap application in Riverside County dropped from 620 wiretap applications in 2015 to 106 in 2016. This is likely due to reforms in the Riverside County District Attorney’s office following a series of investigative reports from USA Today that showed many wiretaps were likely illegal.
  • As in previous years, many of the wiretaps captured voluminous amounts of communications from large groups of people. The largest in terms of communications was a wiretap in a Los Angeles narcotics case in which 559,000 communications were captured from cell phones over 30 days. The largest in terms of number of people were caught up in a wiretap was a Riverside narcotics case in which 91,000 people each had a single piece of communication captured over 120 days.
  • The most expensive wiretap cost $1 million, mostly in personnel costs, to target a single person’s text message in a Los Angeles murder case. The most expensive wiretap in terms of non-personnel resources (i.e. equipment) cost $193,000. Two arrests were made in the associated narcotics case.

Explore the 2016 data [.xls] and the full report. Previous years’ reports are available here [.zip]. Let us know if you discover something interesting in the data by emailing dm@eff.org.  


  • 1. No California county has applied for a wiretap for a pager under state law since 2011.

Via EFF

Featured Image: Dan Wiedbrauk/Flickr