Do it the first time then find a different idea, Or when you are not in the city move it up.
It's fine to block your plate with the plate rim.
But why in the world would someone take a screwdriver or a knife and scrape the plate?
"Oh officer you won't believe what happened, my drill by mistake flew onto my plate and scratched off all the letters...
"
Which part of that story will the officer believe the beginning the middle or the end?
If you spend a few minutes and come up with a creative idea that's your best option.
Like buying a cheap backup camera on eBay and connecting it to your plate in the back where it sits across both screws, feeding the wiring through the trunk to make it as if you actually have a backup camera and then crack the camera(meaning the mounting bracket) allowing it to hang over the plate.
Now you can buy yourself a story and act pissed as if someone broke your backup camera or someone banged into your car causing the backup camera to break...
Or any other creative idea.