If a noise woke me up at 1:30am and I found an intruder coming toward my bedroom, I wouldn't be thinking he's a lost drunk. I would be thinking about protecting my family from a criminal who wanted to do us harm.
So, you are awakened at 1:30 AM and your elderly mother has gotten confused and begun wandering around the house. So, to protect yourself and your mother you shoot the intruder in the hallway bathroom.
Then you turn on the light.
There will be questions and they'll start right away as the EMT's haul away your mother's body.
This will happen in every state ~ even Texas.