Substance versus Procedure
When you look at the law from a distance, you see a maze of rules. This is the maze that ensnared the accused Joseph K. in Kafka The Trial when he tried to determine whether he was guilty of a crime. If you look at the maze more carefully, you find that the rules break down into two general categories, rules of substance and rules of procedure. The substantive rules define the crimes that are punished in the particular state or country. If Joseph K. was guilty of a crime, that crime would have been defined in the substantive rules of the local criminal law. If those rules are secret or too complicated or too vague to understand, then the legal system inhumanely drives people to anxiety about whether they are guilty of a transgression against the rules.
Being guilty is one thing; being prosecuted and punished another. Whether one is ever held liable for a particular offense depends on the rules of procedure. These rules determine how the state enforces the criminal law by proving the occurrence of crime and convicting and punishing those responsible for the crime.
In general terms, we can say that the substantive rules establish "guilt in principle." The procedural rules determine whether individuals are "guilty in fact." Whether guilt in principle becomes guilt in fact depends on several factors--on the evidence available, on the rules for introducing and evaluating this evidence, and on the personalities and talents of those charged with making the decision of guilt. The