Legal Question in Criminal Law in California

This question is impossible to answer without a complete review of all of the evidence in the case. Your lawyer should have this information and is in a better position to evaluate the situation than a stranger on the Internet who knows nothing about it.

There are many reasons a case can be dropped; for instance, your codefendant might have been illegally searched and the evidence against him was thrown out, or the case against you might just be stronger than the case against him. For all I know, he might even have made a deal to testify against you in exchange for dismissal of his charges.

Of course, those are just a few possibilities and your lawyer should know the answer.