Party's senior spokesman Anand Sharma told reporters: "There is a dirty tricks dept in the Bharatiya Janata Party government, which is working overtime tapping phone of opposition, civil servants and judges".
He alleged that the government is putting senior leaders and bureaucrats under surveillance, manufacturing documents, using state agencies and "pliable" sections of media.
Cautioning the government to stop this game of political blackmail, he said it was "spreading canards" and making attempts to "defame".
Wondering as to how classified documents of ministry of defence, of the Central Bureau of Investigation, of Enforcement Directorate, have been selectively leaked to few channels and agencies, he said this created an "incomplete picture".
"The selective leaking and distribution of classified documents creates an incomplete picture. The whole picture is brought out by opposition in Parliament", he said.
He said the government instead of targeting the opposition, should focus on delivering on its promises. "They have failed miserably when you look at the state of economy, job growth, falling exports and falling investment rate".
Turning to the just concluded session, he said budget session has passed 24 laws. It is a record in itself.
Noting that since 2014 when the Modi government assumed office, more than 80 bills have been passed, he said adding that this is "testimony of a mature opposition".
"This is also a rejection of the canard spread by PM Modi that opposition was hindering passage of bills", he said.
Seeking to turn tables on the BJP, he said that many of the bills passed were held hostage by BJP while in the opposition.
At the outset, Sharma targeted the government over the Uttarakhand issue.
"The second half of budget session became a fresh session because of the wrong decision of this government to justify the unconstitutional destabilisation of the Uttarakhand government, by encouraging defection and promoting an environment where money power and the Union’s power were abused," he said.
Giving a word of advice and caution to the government in the backdrop of AgustaWestland issue, he said it should seriously reflect and stop what they are doing and they would "end up seriously compromising defence acquisition and defence preparedness" of the country.
Citing an instance, he said that since the Bofors case, India has not acquired any major artillery system since 1988.
Sharma was sharply critical of the way the Prime Minister Narendra Modi went about on the issue of Rafale fighter deal without the mandate of the Cabinet Committee on Security.
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