A Thames Valley police officer, who emailed secret information on court case witnesses and gangland shootings to his father, has been ordered to do 150 hours of unpaid work.
Matthew Oaten previously pleaded guilty to three counts of computer misuse and two of disclosing personal data.
Winchester Crown Court was told he may have been trying to impress his father, a former police inspector.
PC Oaten was also ordered to pay £1,000 towards prosecution costs.
"Breach of trust"
Thames Valley Police said it was now pursuing a case of alleged gross misconduct against the officer, who is currently suspended from his post in Banbury.
The court was told the force has had to inform the victims about the data breach and faces having to pay thousands of pounds in compensation.
Oaten, of Goodwood Close, Bicester, sent his father the real names and personal details of victims who were giving evidence under false identities in a high-profile child exploitation trial, and emailed details of an ongoing investigation into gangland shootings in the Oxford area.
The 30-year-old officer also illegally checked police files on two previous girlfriends, one of whom was being investigated for leaving her children home alone while she attended a swingers' party.
Gregory Fishwick, defending, said his client's behaviour may have been "simply bravado", an attempt to show off to his father, Russell Oaten, the current chairman of the Dorset branch of Crimestoppers.
Passing sentence, judge Mr Justice Teare said: "These offences were committed in breach of trust, they undermine the confidence the public has that police records will be only used for legitimate police purposes."