Standard notice for a parole hearing is the police department that arrested, the prosecuting attorney's office, and the victim. Sometimes they show up, usually they do not.
Parole hearings, as Soccer Mom, are a lot about the behavior in prison. Has the inmate done the programming expected of him, such as anger management, drug rehab, sex issues, whatever. Further, how many infractions has he had and of what type. The opinion of the unit manager (person in charge of the section of the prison the person is in) is asked his/her opinion. The inmate's plans are given a review, and whether the plan is likely to protect the inmate from temptation.
Inmate can supply whatever information that he can in support of his release. Frequently this involves the inmate having found God, in some form. The inmate can have witnesses at the hearing.
The police department, the prosecutor, and/or the victim are all given an opportunity to speak or submit documents. The closer to being on the line (release/don't release) the more this impacts the decision. However, politics, such as the case with the Manson family, can be a big factor in the impact of these statements.
The state's philosophy on parole is important here. Some states release virtually everybody at their first parole hearing, others don't like to.
Most parole hearings are rather quick and very informal.
Best of luck,
Jim Clark-Dawe