The charges were dropped at the prosecution's request because it is not in their best interest to proceed with counts they can't prove, and it would likely weaken their overall case.
Some of the alleged victims weren't available to testify and other counts were redundant, and most of the dropped charges involved wire fraud that authorities had alleged involved Arneson searching law enforcement databases for Pellicano.
While 28 charges have been thrown out, Anthony Pellicano and former Los Angeles Police Sgt. Mark Arneson are still facing more than three dozen counts. If they are convicted, they will still be sent to prison for a long time.
The Anthony Pellicano case is seen by many as one of the entertainment industry's biggest scandals, but the trail doesn't appear to be living up to it's billing.
Many high profile Hollywood figures have been called to take the stand at the trial, including funny man Chris Rock and former superagent and Disney executive Michael Ovitz.
Pellicano, Arneson and three other co-defendants have pleaded not guilty in the case.
Pellicano, who is representing himself, will begin his defense Friday.