The Eighteen-Minute Blackout at the Grain Market
A commission agent's chest at a grain market in a Punjab town is found short by Rs 8.40 lakh at 13:10, when the day's payments are made. Cash was counted at 12:00 and found correct. The CCTV DVR lost power between 12:28 and 12:48; the inverter fuse in the meter room had been pulled out. Four statements are on record:
- Munshi Balwinder: 'I was at the counter till 12:45, then at the dhaba 200 m away till 13:05. The dhaba owner will confirm.'
- Accountant Karan: 'I left on my scooter at 12:30 for the bank 14 km away, got the token stamped at 12:52 and was back at the mandi by 13:02. My scooter's top speed is 45 km/h.'
- Labourer Harjit: 'I was loading at gate 2 from 12:15 to 12:55.' Five labourers and the weighment register (entries at 12:18, 12:34 and 12:51) support him.
- Chowkidar Gurdev: 'I did rounds at 12:20 and 13:00; both are in the register.' The meter room is 15 m from his chowki and he holds its key.
1. Test each statement against the arithmetic. Whose account does not survive, and what does that prove and not prove?
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Karan's account fails on its own numbers.
- His trip is 14 km each way, so 28 km. At his stated top speed of 45 km/h, 28 km takes at least 28/45 x 60 = 37.3 minutes of pure riding, before any time at the counter.
- He claims to have left at 12:30, been stamped at 12:52 and returned by 13:02 - 32 minutes in all. That leaves 10 minutes to ride back 14 km, which needs 84 km/h, nearly double his scooter's top speed.
- Even the outward leg, 22 minutes for 14 km, requires an average of about 38 km/h - near maximum with no traffic, no signals and no parking time.
What it proves: his alibi as stated is impossible, so his movements must be verified - the bank's CCTV and token register, the scooter's papers, any PCR camera or toll record on the route.
What it does not prove: that he took the money. An impossible alibi establishes that he is not telling the truth about his whereabouts, which is a lead, not a finding.
Others: Balwinder's, Harjit's and Gurdev's accounts are not disproved by arithmetic, but none is yet corroborated from an independent source - the dhaba staff, and the pen and ink of the round register, still have to be checked.
2. Which single assumption, if wrong, would change the whole timeline, and how would you test it?
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The entire case rests on the assumption that the 12:00 count was correct and complete. If a bundle was already short at 12:00, or the count was done by the same Munshi who keeps the books, the loss may have occurred earlier or accumulated over several days, and the 12:28–12:48 gap becomes a coincidence dressed up as a clue.
How to test it:
- Re-count the chest with two independent officers present, and photograph the bundles as found.
- Match the day's receipts against the issue register and the cash balance; a shortage that predates 12:00 usually shows as a mismatch in the previous day's closing.
- Check the bank deposit slips for the previous fortnight for round-figure shortfalls.
- Ask whether the agent has had a shortfall before, and whether the accounts were ever audited.
Second assumption to test: that the pulled fuse and the missing money are one event. A power cut arranged for another reason entirely would make the blackout innocent.
The discipline is to keep the timeline labelled as a hypothesis until the physical and documentary evidence agrees with it - an investigator who announces the answer at 13:30 usually spends the next month proving it.