Maybe it can be, i dunno.
I'll tell my experiences but first:
Reasons no one has any expectation to believe me are I no longer have contact with the friend in question, I do not have any of the evidence below, it's literally my word against everything a person thinks and believes beforehand, etc. So I would never even begin to expect anyone to think I'm not just misremembering or confused or there was something else going on or I was pranked or whatever. I only know what I personally have experienced, and there's literally no way I can prove it. I don't care if anyone believes me or not, and totally accept arguments that I've heard that maybe it was some weird psychosis moment for me and maybe it's all just in my head or whatever. No desire to try to convince anyone.
All that being said there are two events that I have personal experience with that both took place in the same building.
1) When I was 17 I was kicked out of my house by my stepfather, he was abusive, etc but that's another story all together. I stayed with a friend of mine for a little bit because his mom let me. The way his house was laid out was he was on the top floor, there was a middle floor where his aunt lived (widowed). The back enclosed porch area had been converted to his sister's bedroom (she no longer lived at home, it was just my friend and his mom. His brothers and sister had moved out and his dad had died years ago). Anyway my friend was on the phone with his girlfriend so I was just hanging out in that back room giving him some privacy in his room. The entire back of the building was enclosed, so the stairs that led down and all that. Anyway I was sitting in there and I felt a weird feeling so I looked up at the door that led to the stairs that led down (the floors were connected, it was a 2-flat.) I saw a guy looking in at me (it was a door with glass windows, like a porch door basically). I had never seen this guy in my life. I freaked out, I put my head down, I left the room, I went into my friend's room and described this guy because I was seriously in a panic. He said for me to wait a minute and went to another room and came back with a photo that had the guy in it. The guy was his uncle who used to live on the first floor with the aunt. Turns out the uncle had molested my friend's sister in the past. So its like this face peeking into a room that used to be the sister's room. It was weird as fuck. I had never seen the guy before, never seen the picture, didn't even know about the molestation thing, but it was the face that was looking in at me. I know that for certain.
2) We were dorks and thought it would be fun to "ghost hunt" in his building after that because like his dog used to just sit in the kitchen and growl at that back room for no reason, and after the face thing we were freaked. So he had a video camera. A few times we would go down into the stairwell and into the basement area recording in the middle of the night because we were dorks, like I said. Well one time we were recording, it was 1:50in the morning. My friend was spooked and was just like "lets go upstairs man" but I was like "lets just stay until 2:00, that's ten more minutes." He was like "no, we need to go now" so we went upstairs. We were looking back at the tape and there was a voice as clear as day that did not happen while we were down there. The moment I say "that's ten more minutes" there's a voice that says "in ten minutes you're dead" and then my friend immediately "no we need to go now". For the record we were whispering. This voice was not. I heard nothing while we were down there, it was only on the tape.
So those are my experiences that I don't expect anyone to ever believe but I literally have no other explanation for either of these events. I'd entertain any other options because generally I think of myself as pretty scientifically minded and for all I know there really is something that could explain it. But the whole not having contact with this guy anymore (we had a falling out) and not having the tape and all that, I have no qualms with anyone calling BS on me.