He was a race-baiting lawyer and he basically urged the Simpson jury to ignore the evidence and vote their passions. I believe the phrase was "jury nullification", meaning the jury is free to willingly disregard the evidence, because the defense attorney has tagged it as tainted evidence.
Jury nullification has nothing necessarily to do with racism. The jury IS free to disregard the evidence, in each case, every time. Juries are as powerful, if not more powerful, than judges. With all the endless screaming about the corrupt judiciary around here lately, you'd think it would occur to conservatives to remember that.