OJ could have told the world what he really saw that day, even with pictures and/or film and he could have also exposed the drug network that led throughout the halls of California---but he also knew that within that same day no matter what he did his kids would be killed!
While I don't agree with your theory, some in law school I have talked to believe this story or one similar to it, but leaving out drug cartels and implicating LAPD directly.
Looking at both sides, I do admit LAPD were not in their golden years around the time of the murder, and it was somewhat more akin to "Mulholland Falls". There seems to be too much circumstantial evidence against OJ and I don't think even the LAPD could frame anybody that well. The physical evidence either was not there BRD (beyond a reasonable doubt), or the LAPD didn't get the physical evidence together enough to make a BRD case. A guilty verdict cannot be reached when all the elements of a crime(s) are not proved BRD.
As for the civil case against OJ on the same facts, the prosecution only has to prove on a preponderance of the evidence (more likely than not) that OJ did it, and under that more lenient standard, he was found liable.
These are in the historical fact of OJ's previous run ins with the law, but he has little defense on this latest trial. If you want your stuff back, do not use deadly force, or basically, don't bring a gun to a knife fight because the courts will jack you on that one, regardless of who was right or wrong in the beginning.