Truth vs Hype: Coal scam - Tampering with the evidence?

There have always been serious doubts about how much freedom the CBI will have in its investigation into the coal allotment scam, given that it entails probing the role of senior ministers, including the the Prime Minister, was holding the coal portfolio during the time the controversial allotments were made. And so when news came it that the Law Minister may have tampered with the CBI's coal scam status report, meant only for the eyes of the Supreme Court, it confirmed widespread fears. The government was quick to deny the charge of tampering, saying that these meetings were only to discuss a technicality. But this week, our investigation reveals that the scope of interference went beyond just the law ministers, involving top law officers and even officials from the PMO. Is this why the CBI's probe into the coal scam so far is only limited to action against lower level government officials, instead of going up the ladder of accountability?