>> I'm not a psychologist but this guy reads like a stock standard psychopath. https://en.wikipedia.org/wiki/Psychopathy

This isn't a strong assertion and hence doesn't need a water tight argument or strong evidence. It notes I'm not an expert in the field, and that I'm basing the judgement on the writing only. Not everything is an academic paper or a judgement from a jury.

That being said, read the section on "core traits" in that link and read the article again. Lack of remorse... arrogance (the abs section?) and impulsive behavior (he murdered someone and is in and out of the hole for 30 years....).