Not a deterrent or reliable witness.

Attacker thinks "Video" not "streaming email"
For security purposes my lock screen is set to ONE MINUTE before requiring pass code or fingerprint.
In times of stress/duress its too much to have to go to settings and change it to "never" during the incident.
Often times you can de-escalate a situation by talking calmly and cooperating.
If attacker THINKS they are being recorded, it WILL escalate the situation and cause them to target the phone as well.
As it is now, when lock screen engages, "incident" ENDS.
If attacker separates you from phone, no more witness. Yeah someone somewhere knows you WERE in trouble but thats of little comfort.

Eyembeajay about EmergenSee