The entering of a nolle prosequi by the Director of Public Prosecutions means that he is not pursuing the prosecution at this stage. Theoretically he may pursue the prosecution at a later stage, but this rarely, if ever, happens.
Normally the DPP does not give a reason for such a decision, but it is usually based on a problem with the evidence he has assembled. In the course of assembling it, or after it has been assembled in a book of evidence, a problem may arise with a witness or a crucial part of it, that would make it difficult to proceed.
Difficulties of this nature usually undermine the whole basis for the trial. Even if new evidence is discovered, the problems with the old evidence remain. If a nolle prosequi is entered, and then registered by the court, the accused is discharged and free to go.
He or she enjoys the presumption of innocence that all accused people enjoy until they are convicted of a crime beyond all reasonable doubt.
The entry of a nolle prosequi yesterday in the manslaughter case against Dermot Laide, therefore, means that he is innocent of this charge.