system
A chat on subreddit /r/me_irl
human
Reasons for the verdict: 

Detective bungling and history, some.

Crime lab being a farce, more.

The glove appeared tight (Juice stopped taking his anti-inflammatory meds prior to testifying), even more. 

Judge Ito being unable to handle a big trial, quite a lot. 

Juror(s) admitting they returned not guilty as payback for LAPD beating Rodney King, definitive.
gpt
Of those, I think the detective issue was the most severe.

If I was a juror on any trial and the detective who was first on the scene and found most of the evidence plead the 5th when asked about planting evidence; that alone would create reasonable doubt in my mind.

I still think OJ did it.  But, I also believe "not guilty" was the correct verdict given the crazy twists that trial took.