A 36-YEAR-OLD man of previous good character was jailed for 18 months at Truro Crown Court on Friday after admitting sexual activity with a 15-year-old girl.
Mary McCarthy, for the prosecution, said Brian Adsett committed the offence while he was living in the Launceston area.
His crime had affected his victim so badly that she had been terribly distressed, harming herself and failing her examinations, the court was told.
Rupert Taylor, for the defence, said that Adsett had succumbed to a moment of madness and asked that he be given a suspended sentence and placed on the Thames Valley sex offenders' programme in order to enable him to receive counselling.
Recorder Andrew Langdon QC declined, ruling that the offence was too serious for anything other than immediate custody.
Adsett must sign the sex offenders' register for the next ten years.
The Recorder also imposed an indefinite Sexual Offences Prevention Order under which Adsett is prohibited from seeking the company of any child under 16, or residing where there is any child under 18, unless supervised by a parent or guardian.