What will happen to mDPM.lockNow(); if there is no security pin on android device?

Question

If a user has not put a security pin on her device, and my app even if it has device admin privileges sends a mDPM.lockNow(); to remote lock the mobile, what will happen?

Answer 1

It will just lock the device! The user can simple unlock normally.

mDPM.lockNow()

is only to lock the device (regardless of the fact that PIN exists or not)