"Silvio Berlusconi must be acquitted because he has committed no crime," Niccolo Ghedini told the court ahead of a verdict later this month in the trial, which has lasted more than two years.
He said Berlusconi had simply been "humane" by giving money to the girl in question - then 17-year-old Karima El-Mahroug, better known by her nickname of "Ruby the Heart Stealer".
Prosecutors have asked that the 76-year-old Berlusconi be given a six year prison sentence and be banned from holding public office for life.
Ghedini accused prosecutors and judges in the trial of having "prejudices" against his client.
Berlusconi has said prosecutors are left-wing and out to get him and he denies all charged.
A verdict in the trial is expected on June 24th.
Berlusconi is accused of putting pressure on police to have El-Mahroug released from custody when she was arrested for petty theft.
Ghedini said Berlusconi thought El-Mahroug was related to then Egyptian president Hosni Mubarak and wanted to avoid a diplomatic incident.
The trial revolves around allegedly raunchy parties hosted by Berlusconi at his luxury villa near Milan, attended by dozens of young women.