James Andrew Hardy was previously found guilty of misfeasance in a public office for improperly accessing the police database and was not jailed. He was given a suspended prison sentence of 28 weeks and 300 hours of community service.
The Attorney General appealed that sentence and the prison term was increased by the Court of Appeal to nine months.
Hardy accessed the police database and passed personal details on three people to Martin Jolley, a known criminal. Jolley wanted to take action against the three in retaliation for their actions against him or a friend.
Hardy must have known, said judges Lord Chief Justice Lord Phillips, Mr Justice Hedley and Mr Justice Pitchers, that there was a serious risk that Jolley intended to subject the three people to physical violence.
The judges ruled that the sentence should include an element of detrrent in order to make it clear to other police officers that the improper use of information in the police database was an offence that would be severely punished.
Hardy and Jolley had both pleaded guilty, and the judges said that taking that into account Hardy should face an 18-month jail term. Hardy had already served the equivalent of a 10-week jail term while awaiting trial as well as a four month curfew. He had also already completed his 300 hours of community service, so the Court ordered that he complete a nine month jail term.
Special constable Geraldine Tabor was fined £1,000 in 2005 for looking up the criminal records of fellow employees at the petrol station where she worked. Special constables are part-time volunteers. She said she looked up the details because she suspected one employee of stealing fuel and the other of stealing bags of chocolate oranges.
In 2004 a police computer operator was fined £400 under the Data Protection Act for using the police database to look up four of her friends because she was bored.