Highly placed officials said the sanction to prosecute Singh in the disproportionate assets case under the Prevention of Corruption Act, was refused by the Speaker recently.
The case is being probed by Special Investigating Team of the Mumbai police for the last three years.
Officials said the decision of the Speaker has been communicated to the Police team which had sought permission for prosecution. "The decision is open to court's scrutiny," officials pointed out. Activist Sanjay Tiwari had filed a case with the Anti-Corruption Bureau and also a PIL in Bombay High Court alleging that the Congress MLA from Kalina had amassed wealth disproportionate to his known sources of income.
A SIT, then headed by Mumbai Police Commissioner Satyapal Singh, had completed investigations in the disproportionate assets case last December and sent its report to the Speaker seeking his approval to prosecute Singh as is required under the Prevention of Corruption Act.