LET US imagine a country called 'Theory'. This place has a well equipped police force, which interacts well with the rest of the population, and it has little work to do. Most of their work comes because of calls from the citizenry, indicating suspicious behaviour. With speedy response to these communications, most of their duties consist of what could best be described as preventative policing. Those who do wrong are quickly apprehended and brought before the court.
Witnesses willingly come before the judge to assist in the administration of justice.
In the appropriate courts there is a wide selection of jurors available to expedite the process. Capital punishment is part of that country's legal system, but it is seldom prescribed. On the few occasions that this happens the executioner also does his job speedily. In theory, the police and the judge and the jury and the executioner all exist. In fact they co-exist well, and fully understand the importance of their respective roles in supporting each other.