Samsung Galaxy S7 User Manual page 72

Secure Lock Screens
You can make calls even if your phone has a secure lock screen.
Note: The first step differs depending on the device and Lock screen
settings.
1. Drag Phone upward to open the call screen.
2. Tap Emergency call to display the Emergency dialer.
3. Enter the emergency telephone number (911 in North America)
and tap
4. Complete your call. During this type of call, you have access to
most in-call features.
Calling
Dial.
61 Emergency Calls