The justice system is a complicated process and deals with not only finding the people who commit crimes, but also convicting and judging them. There are a lot of different areas that make up the entire justice system and in science fiction we see these areas dealt with in very different ways.
In some stories it is about compressing the process, in that way justice can happen more swiftly and not have to deal with the lengthy processes of trials or other things. Another option that can be found in science fiction is creating some sort of automated or surveillance-based system. The basic idea is that someone is always watching and keeping track. Both of these futures look to hasten the path to justice, but at a cost.
Cop, Judge, Jury
The obvious reference for a science fiction justice system are things such as Judge Dredd or Robocop. In these situations someone or something finds the criminals, decides their guilt, and passes the sentence. A lot of time this occurs because crime has risen to such a level that justice needs to happen swiftly in order to deal with the growing number of criminals that are out in society. This means that a person is trained to do every step of the process instead of having one person to arrest and investigate, another to decide to go to trial, and then a judge to pass sentencing. It narrows the process down to one person to speed up the process.
In a few science fiction stories they look at justice as the need to watch things at all times. This can be seen in Minority Report (in a way) and in the surveillance system set up in Captain America: The Winter Soldier. Now each of these stories add an additional level of judging a crime or criminal before it happens and basically convicting before a crime happens. At the same time the idea is still their that surveillance is used as the ultimate justice system.
The idea that we can track citizens at every moment could mean that we could track the actions and give tickets and sentencing based on those actions. Now imagine that it is not external surveillance, but something that gets imbedded underneath the skin of each individual. Something that could track you and automatically send a signal to the police or automatically take fines out of your bank account, points off your license, etc. Something like in Fifth Element when his car was deducting points from his license as he drove.
Obviously the extreme problem with all of this is can either of these solutions really be called justice? Both of them are quick to convict and not take the time to fully examine or look at a situation. It is about the swiftness of justice instead of the ethics or morals of justice. What do you think?