A special bench headed by Justice D K Jain ordered the CBI to forward the samples to All India Institute of Medical Sciences to ascertain the cause of his death on Saturday.
The bench, also comprising Justices V S Sirpurkar and G S Singhvi, further directed that the judicial magistrate inquiring into the circumstances leading to Asthana's death shall submit his report to it within eight weeks.
The apex court also asked the UP police to provide adequate protection to all the accused and witnesses in the case in which some judges were allegedly involved.
Asthana, who was a treasury officer at the Ghaziabad court, was arrested in April 2008 in connection with siphoning off provident fund of class III and IV employees. During interrogation, he had named 36 judges of various courts, including one from the Supreme Court, as alleged beneficiaries of the scam.
CBI is investigating the case under the directions of the apex court.
Those names in the scam include seven Allahabad High Court judges, six retired High Court judges and 12 judges of subordinate judiciary in Uttar Pradesh.
The apex court, however, turned down the plea for a probe into the death by an impartial retired police officer as sought by Nahar Singh Yadav, president of Advocates Welfare Association, Ghaziabad.
It was on Yadav's petition that the CBI was ordered by the apex court in September 2008 to probe the case.
"There cannot be a parallel inquiry, we will see later," the bench observed when counsel Prashant Bhushan submitted that retired DGP Prakash Singh or former IPS officer Kiran Bedi should be entrusted with the investigation.
Bhushan argued that such an inquiry was essential to inspire public confidence in the investigation since a number of judges were also allegedly involved in the scandal.
The counsel submitted that inquiry by a judicial magistrate or by the Uttar Pradesh police may not inspire the same confidence as the local police itself had earlier gone on record that they would prefer a probe by the CBI into the scam.
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