The commission said Mr Chavan failed to file his election expenses in the manner as required by the law.
The Election Commission order came on the complaint of former Maharashtra minister Madhavrao Kinhalkar, who was defeated by Mr Chavan from Nanded in 2009, and the BJP.
The complainants said Mr Chavan had not included the expenditure for 25 advertisements in Marthi newspapers in his accounts.
The Congress leader tried his best to stop the Election Commission from probing this case by first approaching the Delhi High Court and then the Supreme Court, but failed.
The Election Commission in its 104-page order says, "The commission is of the considered view that respondent (Ashok Chavan) cannot validly claim ignorance about the publication of the above-mentioned 25 advertisements in which his name, the name of his constituency and also his photograph prominently appeared."
Mr Chavan, meanwhile, said the notice has vindicated his and Congress' stand and "there is no question of paid news." (Issue of Paid News is Ruled Out: Ashok Chavan on Election Commission Notice)
The commission has also cautioned the media and asked them to be more responsible by saying, "The minimum that is expected of ethical journalism is that the reader is cautioned by suitable disclaimers while such articles are published so that the unwary reader can make suitable allowance in his mind while forming his judgement. This matter assumes greater significance in the election period when the media needs to show greater responsibility."
Mr Chavan came out of the Adarsh scam, but is now caught in the paid news issue. The Election Commission finding him guilty is the first step towards his disqualification. If the commission disqualifies Mr Chavan, he can't contest for the next three years and importantly will lose his present seat in the Lok Sabha.
If Mr Chavan is disqualified, it will bring further ignominy to Congress which has won just two Lok Sabha seats out of the state's 48 in the national elections held in May. The party's tally will then be reduced to just one.
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