As Delhi choked on the intervening night of October 20-21, the raw data recorded by monitoring stations painted a picture of an air quality apocalypse: 959 at a station near the Supreme Court of India; 892 at Ashok Vihar; a crippling 998.8 in Chandni Chowk. But, even as 22 of 39 stations crossed the severe plus category of air pollution by 10.45 pm, the official tracking system began to buckle.

India Today’s analysis into the Central Pollution Control Board data for the critical 48-hour period found that throughout the darkest hours of the smog on Diwali night, fewer than a third of the monitoring stations — just 11 — were recording continuous data, leaving vast, suspicious gaps in the official record of the city’s air emergency.

Of the 39 functional monitoring stations, only 11 record

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