My friend is being charged for murder. The only evidence they have is a witness who statement has changed several times. He had 7 pretrial conferences and after the last one that decided to take it to trial anyway which is a year from now? Is it something his public defender could do to change this? This is in Philadelphia

Not really the DA makes the choice if they are going to trail or not. At some point the grand jury had to decide there was enough evidence to take it to trial.

During the period till the trial, they will be looking for more evidence