BROOKLYN - Reverend Al Sharpton held a rally Saturday denouncing the promotion of a NYPD officer involved in a controversial fatal shooting back in 1999.

A ceremony was held on Thursday for Kenneth Boss to promote him from officer to sergeant.

Boss was one of the four officers acquitted in the fatal shooting of Amadou Diallo.

Diallo was killed after being shot 41 times. 

Police say Boss' promotion is mandated under civil service law because he passed the sergeant's test and wasn't under any type of investigation.