The Government has been accused of a "cavalier" attitude to personal information after it emerged that four CDs containing details from court cases have gone missing in the post.
In the latest embarrassing loss of potentially sensitive data, the computer discs vanished after being sent by recorded delivery.
Greater Manchester Police (GMP) hand-delivered the four CD-Roms to Her Majesty's Inspectorate of Court Administration (HMICA) on December 6.
The discs contained details of at least 55 magistrates' court defendants and other "restricted" data not released in open court, the Daily Mail reported.
They went missing after being posted on December 15, according to the paper.
A GMP spokesman said the CDs contain only "routine material" and were handed to HMICA by police in a "completely secure way" before going missing later.
The police spokesman could not confirm whether the discs contain details of witnesses, although he said they may have held defendants' names.
HMICA has launched an internal investigation into what has happened to the discs.
Shadow justice secretary Nick Herbert said: "Yet another data blunder suggests a cavalier attitude to the handling of personal information by Government agencies.
"We need to know whether this is a problem limited to these courts, or whether it is more widespread across the criminal justice system."
