A medical file listing the reasons why police constable Mario Portelli was boarded out (cleared not to work for medical reasons) from the corps will have to be exhibited in court as part of the case against lawyer and former police inspector David Gatt.

Mr Portelli, who became known by his police number PC 99, is the star witness for the prosecution. He was boarded out five months ago.

Dr Gatt stands charged with a string of high profile hold-ups, including masterminding the hold-up at HSBC headquarters in June 2010 and another on a jeweller in Attard that December.

In previous court sittings Mr Portelli testified that Dr Gatt was behind the robberies, which went as far back as 2007 when thieves made off with €1 million in a heist on the HSBC Balzan branch.

The defence had queried whether Mr Portelli had ever been held at Mount Carmel psychiatric hospital, which the officer denied.

In today's sitting Assistant Commissioner Mario Spiteri, who works at the police human resources department, testified that Mr Portelli was boarded out from the police force five months ago.

A board composed of three doctors accepted the medical reasons for Mr Portelli's boarding out.

Magistrate Tonio Micallef Trigona ordered AC Spiteri to produce the medical file in the next sitting.

Lawyer Joe Giglio is appearing for David Gatt while Police Inspectors Joseph Mercieca and Michael Mallia are prosecuting.