In the past, several cases of abuse and foreclosure of law had taken place. Convictions unfair or without the right to ample defense. Disproportionate penalties. Condemnations by political poets, etc.
Due process is one of the democratic achievements guaranteed by the Constitution. In a democracy, all citizens accused of a crime have the right to a lawyer, ample defense and an exempt judgment, being able to resort to other instances to curb any kind of excess. The Law also applies to all citizens, regardless of color, gender or social class. Ordinarily, everyone must respect the laws in the same way.