Kill switch mandates suffer a variety of flaws that CDT has discussed previously. However, the California bill is especially troubling on the issue of police using the feature to shut down phones.  The legislation states that government agents may use the kill switch so long as their activities comply with Section 7908 of the Public Utilities Code.  This law allows governments to disrupt communications under certain guidelines with judicial authorization, but also includes an "emergency" exception that requires no independent approval.

Police could use the kill switch to shut down all phones in a situation they unilaterally perceive as presenting an imminent risk of danger.

This means that police could use the kill switch to shut down all phones in a situation they unilaterally perceive as presenting an imminent risk of danger.  It's not hard to imagine law enforcement putting such a label on a protest: