There was information in the Lisa Norrell case that was blacked out and removed from documents prior to their release.
http://journalism.berkeley.edu/projects/lisa/records.html
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Public Documents Remain Sealed
Such official secrecy, and the inaccessibility of what are normally public documents (See HOW-TO), have given rise to questions about why the Contra Costa County District Attorney's office dismissed charges against Shoemake, even though police have yet to charge a suspect with Lisa's murder. At one point police arrested two Pittsburg men, David Heneby and Garry Lee Walton, as suspects in the case. However, police released Walton the very next day and never charged either man with the murder, citing a lack of evidence.
Indeed, the mysterious circumstances of Lisa's murder are echoed by strange turns in the investigation itself, which is led by a two-man team of homicide detectives working out of an office in a temporary trailer at the Pittsburg police station.
The past year has seen other widely covered killings of young Bay Area women, from San Francisco to Yosemite National Park, eventually result in the arrest and arraignment of suspects. Lisa's murder remains a glaring and painful exception.
Many in this working-class town of 54,000 are anxious and upset. They wonder why the case remains unsolved. While the questions are many, the answers are few: How exactly was Lisa killed? What, if anything, did Shoemake know about the murder? And why do the police resist offering even the slightest details about the investigation?
The authorities, who have given only a heavily censored version of the coroner's report and have tightly restricted access to search warrants and other records, say they are only doing their utmost to ensure that the probe is not hampered by outside interference. Their requests to seal all public documents usually open to the public have been sustained by Contra Costa County Superior Court judges.
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