The direction in this regard was issued by Justice K Harilal while considering a petition by K T Michael, former superintendent of police, alleging lapses on the CBI's part.
Michael alleged that CBI's investigating officer had charged that he (Michael) had destroyed the material objects, including the personal diary and veil of Sister Abhaya.
Though CBI found that the case was homicide, investigation was not pointed towards material objects.
The high court, appreciating the contentions of the petitioner, directed CBI special court to return the final report and documents which the investigating office required for further probe.
The court clarified that such reports would be considered as supplementary reports only.
Justice Harilal also directed that trial would be postponed till filing of further reports.
Earlier, the CBI special court at Thiruvananthapuram had rejected the plea of the petitioner, which was set aside by the high court on Thursday.
The court also directed CBI to find out whether there had been a willful destruction of the case properties with an intention to cause disappearance of evidence, or to save the offender from legal punishment by the public servants in the office of sub divisional magistrate, Kottayam or investigating officers or anybody else who dealt with case properties.
The body of the 19-year-old nun, an inmate of St Pius convent, Kottayam, had been found in the well of her convent.
While the crime branch concluded it was a case of suicide, the CBI, which took over investigation, concluded that Abhaya was murdered. However, they sought closure of the case for lack of evidence, which was turned down by the court.
On Nov 19, 2008, two priests and a nun were arrested by CBI for murdering Abhaya. In 2009, charges of murder, destruction of evidence were filed against the three accused.
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