Q: Can 2 people be convicted of distribution of marijuana or distribution of controlled substance.

A: It depends on whether or not that person was part of the sale/distribution. If A tells B to go sell drugs and B sells to C then yes. If A lives in a home where one of the roommates deals drugs and A has nothing to do with it then A would not be found guilty on those facts alone.

It is possible for the Commonwealth to get a trial by jury, so yes, they can try your case by jury even though you waive your right to a jury trial.

A: Absolutely! As long as the other person played some part in the sale, he can be found guilty. The part can be as small as driving the seller to the transaction. It can even just BEING THERE, if the prosecutor can prove to the jury or trier of fact that the second person furthered the transaction in some way by his presence, such as if his mere presence helped provide security for the seller, or discouraged potential buyers from robbing him. Of course, if the second person provided the drugs to the seller, he could be found guilty of distribution even if he is not present at the time of the sale.

As far as a jury, yes, it takes two to tango, but only one to demand a jury. Even if you waive your right to a jury (for some inexplicably STUPID reason) , the prosecutor can still demand a jury trial. However, this rarely happens. Prosecutors would usually rather try a case to a judge than a jury in almost any situation. They know that judges find people guilty roughly twice as often as juries do.