How does a preliminary hearing protect me from unlawful arrest and detention?

The Commonwealth must show that your arrest meets the minimum requirements established by law. At this hearing, the Commonwealth must make at least a prima facie case – that is, at least a minimal showing – that a particular crime was committed and that you are probably the one who committed it. At this stage, the Commonwealth doesn’t have to prove your guilt beyond a reasonable doubt. In order to meet its burden, the Commonwealth must only present some evidence regarding each of the material elements of the crime charged. If the government can’t meet this burden, your case will be dismissed.