How in the world did the 3 police officers in the Sean Bell case get acquitted?

I am very disappointed in the judical system this morning. In 2006 after Sean Bell and two of his friends were leaving his bachelor party at a New York strip club.They got into a verbal confrontation with club bouncers (who happen to be New York police officers). As they were getting into there vehicle to leave the police officers fired 50 shots at them killing Sean Bell and wounding the others. The time the police officers thought that Sean Bell and his friends were armed, but they were not armed at all.