Presumption of Guilt.

Ammianus Marcellinus relates an anecdote of the Emperor Julian which illustrates the enforcement of this principle in the Roman law. Numerius, the governor of Narbonensis, was on trial before the Emperor, and, contrary to the usage in criminal cases, the trial was public. Numerius contented himself with denying his guilt, and there was not sufficient proof against him. His adversary, Delphidius, “a passionate man,” seeing that the failure of the accusation was inevitable, could not restrain himself, and exclaimed, “Oh, illustrious Cæsar! if it is sufficient to deny, what hereafter will become of the guilty?” to which Julian replied, “If it suffices to accuse, what will become of the innocent?” Rerum Gestarum, L. XVIII, c. 1.

This is analogous to the principle of presumption of innocence. The legal idea that every accused person is afforded an opportunity to defend them selves through the due process of the law before and only after that process should conclusions be drawn about their guilt.
This ideally should safe guard innocent citizens caught up by the vicissitudes of life. To say: wrongfully or maliciously arrested.

However, is the Presumption of innocence realised in the operational field of the criminal justice system?
The overuse of pretrial detention besmirches the notion. The biggest numbers of prison inmates are actually on remand. Mostly because the police files on the accusations against them are either lost or ‘still being processed’. While in the cells persons may pick up habits; violence, gangbanging, homosexuality to mention but a few.
By their release upon the expiry of the 60 remand days, the sanctuary for quarantining crime has perhaps turned them into missionaries of vice. Before you know it their arrested again(rightly so) and the cycle continues. A once innocent person has been transfigured into a will-always-be-guilty.

The withered presumption of innocence is infact a presumption of Guilt and the system turns it to an assurance of Guilt.