Legal Question in Constitutional Law in Pennsylvania

Re: subject

They choose cases based upon the legal issue involved. Usually to clear up a disagreement among circuits (US Supreme) or related to lower courts (PA). They are choosing cases that involve issues that they believe need to be clarified.

It would be impossible for either of them to accept all of the cases filed for appeal. There's just too many of them.

Re: subject

The U.S. Supreme Court is asked to review thousands of cases each year. There is no way a single court could decide so many cases. At best it can handle about 125 per year, and it usually doesn't take even that many. The Court selects those cases based upon the importance of the legal questions they raise and is less interested in whether the case was correctly decided by the lower court. Even egregious errors usually won't be reviewed if the legal issues involved are clear but were merely applied incorrectly.

I presume that the Pennsylvania Supreme Court works much the same way.