That's why we have three degrees of judgment.Well, the criminal trial was won by the defense because they were able to convince the jury that the cops had framed O.J. by allegedly falsifying the DNA evidence. Jurors also considered that evidence relating to Simpson's history of domestic abuse was not relevant to the case. So, once the DNA evidence and the history of domestic violence were disregarded by the jury, there wasn't much left to convict him.
So, in one trial, some people decided the evidence was "false," while other people in another trial decided the exact same evidence was "true." If the DNA evidence was declared tainted and inadmissible in the civil trial, then the result would have been the same as in the criminal trial.
There's the Court of Assizes, the Court of Assizes of Appeal, and the Supreme Court (called Court of Cassation).
Then the Court of Cassation can forward the case to another Court of Assizes of Appeal, so there can be even 5 degrees of judgment.
Because a popular jury can be biased and partial. That's why.