No, once you have formed the idea that the person is involved they are a suspect. They might interview him and find out he was frightened by a mountain lion and running for his life. And be able to prove it. In that case he would be downgraded from suspect to witness possibly but guaranteed, if police contact him and start interview him they will read him his rights. That is because they have already formed in their mind that he was involved. There is no difference tween a suspect in a person of interest. Give me the detail if you think otherwise
I understand, which is why I defined person of suspect as a person who may have knowledge, without being involved in the crime itself.
I only said that it often means suspect, but they can’t formally call the person that unless they have proof that they can call him that.
The term itself does not mean suspect. It’s just most of the time the person of interest becomes a suspect, statistically speaking.