Lock profile pictures via API?

Community Novice

We are currently pulling profile photos into Canvas from our on-campus ID card system by updating the avatar URLs via API as part of our nightly scripts. However, users can still change their picture in the Canvas GUI because they are not locked. While these user-uploaded pictures are overridden each night with the official photo (leaving little room for disaster), the fact that they have the ability to change it is causing them to think something is "wrong with Canvas" when it reverts overnight.

Is there a way, via the API, to bulk "lock" profile pictures or to lock them as we update them via our script?