The Supreme Court on Monday said it will hear on April 1 a petition filed by 21 Opposition parties to verify at least 50% of the votes cast in the Lok Sabha elections using the Voter Verified Paper Audit Trail machines.

The top court asked the Election Commission to file an affidavit by 4 pm on Thursday explaining why verification of ballots through paper trail should not be extended to more than one polling station in every Assembly segment, ANI reported. The petition challenged the poll body’s decision to verify ballots cast at just one randomly selected booth in each constituency.

Chief Justice Ranjan Gogoi and Justice Deepak Gupta heard the matter. “We are asking a simple question – can you increase the number of VVPAT machines?” asked Gogoi, according to Live Law. “Every institution, including judiciary, must be open for suggestions. If you can’t increase the number, file affidavit.”

The bench indicated that it wanted the number of VVPAT machines to be increased, saying it was not a question of “casting aspersions” rather it was a matter of “satisfaction”, PTI reported.

The parties that have approached the court include the Congress, Andhra Pradesh Chief Minister Chandrababu Naidu’s Telugu Desam Party, Sharad Pawar’s Nationalist Congress Party, Aam Aadmi Party, Communist Party of India (Marxist), Communist Party of India, Derek O’Brien for the Trinamool Congress, Farooq Abdullah for the National Conference, the Samajwadi Party, the Bahujan Samaj Party, the Rashtriya Lok Dal, Sharad Yadav’s Loktantrik Janata Dal, and the Dravida Munnetra Kazhagam.

The parties want stricter standards and safety norms instituted to prevent tampering of electronic voting machines.

Opposition parties have raised doubts about the credibility of electronic voting machines a number of times in the last two years. However, the Election Commission has repeatedly denied allegations that the machines can be tampered with.

On January 24, Chief Election Commissioner Sunil Arora reiterated that the country would not revert to using ballot papers for elections.

The Lok Sabha elections will be held in seven phases from April 11 to May 19, and the results declared on May 23.