Have I ever told you I see old Joe every day I walk to work?
Why do you see him every time?
I try to keep an eye on him.
You are really looking out for your health by walking, which is great! But I don't think Joe appreciates you constantly watching over him. He is  a human, not a prisoner.
But I need to follow him since he keeps trying to cause harm and he just got out of prison yesterday.
I understand your concern that he may cause problems around the workplace. But it's not your responsibility to keep an eye on him. If you feel concern you should bring that up to somebody that could take care of the issue.