An indictment sets out the prosecutor’s case against the people that he believes are responsible for the crimes charged in the indictment. It does not establish any individual’s guilt.
Sealing the indictment, i.e. preserving its confidentiality, shields an accused from the stigma of being associated with a crime when the pre-trial judge ultimately may not confirm the indictment due to lack of evidence. Upon confirmation, the indictment may remain sealed to secure the participation of the accused at trial. The authorities responsible for executing arrest warrants are more likely to be successful if the accused does not have an opportunity to abscond or otherwise evade arrest.