Special Judge Arun Bhardwaj said that Swamy has no locus-standi to file the application and dismissed his plea seeking to bring on record a vigilance report on the alleged tampering of evidence in the case.
"...in the opinion of this court the applicant has no right to file the application for calling the report of the vigilance enquiry for satisfying whether the short comings observed in the report were considered, investigated, prior to preparation and filing of chargesheet," the judge said.
The court also observed that cognisance has already been taken against the accused.
It noted the court cannot give direction for further investigation as it is upto the agency to decide if further probe is required or not.
"After the cognisance has been taken by the court, it cannot direct further investigation and only the investigating agency concerned has the power to undertake further investigation," the judge said.
The court was hearing the case against Congress MP Shashi Tharoor, accused of abetment to suicide of his wife Sunanda Pushkar.
Swamy has told the court that there is certain evidence which is required in the case. He told the court that some people had gone to "extraordinary extent" to "make sure that the evidence was destroyed."
But Tharoor's counsel and senior advocate Vikas Pahwa has opposed the plea and said that Swamy has no locus standi in the case because he is neither associated with the prosecution nor with the accused or the victim.
Swamy responded that he has locus in the matter as the chargesheet in this case was the outcome of his public interest litigation filed in the higher court.
Defence counsel Pahwa said public suits did not grant anyone the right to be a part of a trial.
Pahwa also said that all the allegations on destruction of evidence were false.
Additional Public Prosecutor Atul Shrivastava has also opposed Swamy's plea and raised question over its maintainability.
On May 14, 2018, police chargesheeted Tharoor under Sections 306 and 498A of the Indian Penal Code, pertaining to abetment to suicide and cruelty to wife, which entail a jail term of up to 10 years.
Pushkar, 51, was found dead under mysterious circumstances in a hotel room in south Delhi on January 17, 2014, days after she alleged that Tharoor was having an affair with a Pakistani journalist.
( With inputs from IANS )