Blue Shirt at the Junction: Testing Three Alibis Against the Clock
A house in a Palakkad village is found at 17:00 with its front door latched from outside; the family left at 13:50 for a wedding. A bedroom jewellery box is empty: 5 sovereigns of gold and ₹40,000 in cash are reported missing. The front door lock is intact and shows no force; a rear window grille has two freshly cut bars. The house stands on a lane whose only camera, at a shop 90 m away, covers the junction with the main road.
The camera shows a man in a blue shirt entering the lane at 15:12 and leaving at 15:41 with a cloth bag. Statements: (A) 'I was at the taluk hospital from 14:30 to 16:00' - token record 15:05; bus travel between hospital and lane is 30 minutes each way. (B) 'I was at the ration shop, then home' - the shop's UPI log shows a payment at 15:50; travel from shop to lane is 12 minutes. (C) 'I was at the town bus stand, 26 km away, from 14:20 to 16:00' - gate camera shows C at 14:22 and boarding at 15:58; the fastest bus takes 50 minutes one way.
1. Which of A, B and C can be placed in the lane during the theft window of 13:50 to 17:00? Show the arithmetic and state what follows for each suspect.
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Convert each alibi into a window of possible presence.
A: the only hard evidence is the 15:05 token. Leaving immediately, A reaches the lane at 15:05 + 30 = 15:35, inside the theft window. So A cannot be excluded - but A cannot be the man who entered at 15:12.
B: payment at 15:50 plus 12 minutes' travel gives earliest arrival 16:02, inside the theft window. So B cannot be excluded - but B cannot be the man who entered at 15:12 or left at 15:41.
C: earliest possible arrival in the lane = 14:22 + 50 = 15:12. To board at 15:58, C must leave the lane by 15:58 − 50 = 15:08. The earliest arrival (15:12) is later than the latest possible departure (15:08), so C cannot have been in the lane at all.
Conclusion: C is excluded. A and B remain possible as accomplices or lookouts, but neither fits the camera. The blue-shirt man is therefore an unaccounted-for fourth person and is the primary lead - not a reason to release A and B from suspicion.
2. The door was latched but not forced, while the rear grille was cut. Set out two competing hypotheses and the specific evidence that would separate them.
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The physical picture suggests entry at the rear and exit at the front, with the front door pulled shut and latched from outside to delay discovery - which requires no key at all.
Hypothesis (a): an outsider cut the grille, entered, and left by the front door, latching it behind him. Hypothesis (b): someone with legitimate access staged the break-in, using the front door normally and cutting the grille to manufacture a narrative.
What separates them: whether the family locked the front door with a key or only latched it (take separate statements, not a joint one); fresh metal filings and tool marks on the cut bars, and whether both cut ends match a single blade; dust and footmarks on the window sill and in the rear yard; fingerprints on the inner latch and on the jewellery box; whether the rear grille shows old rust at the cut or bright metal; and whether anything was taken that only a household member would know about.
Practical instruction: the grille must not be repaired and the room must not be tidied before photographs and a mahazar.
3. The shopkeeper offers to send the CCTV clip on WhatsApp. Explain the correct handling of this electronic evidence and the risks of the shortcut.
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Refuse the WhatsApp copy as the evidentiary record. It is compressed and re-encoded, its metadata is altered, and it will not survive scrutiny.
Correct route: obtain the DVR or its hard disk, or a direct export from the DVR onto a fresh pen drive; seize it under a mahazar with two independent witnesses (Section 106 BNSS, earlier Section 102 CrPC); note make, model, serial number and the DVR's clock time, and calibrate that clock against a known reference, since DVR clocks drift by minutes and the whole case here turns on minutes; record the exact time span exported and confirm the camera's field of view covers the lane junction.
If a working copy is made, compute and record a hash value, keep the original sealed, and obtain the certificate required for electronic records (Section 63, Bharatiya Sakshya Adhiniyam, 2023).
Timing risk: shop systems usually retain footage for only 7–15 days, after which it is overwritten. Seize and export on the same day, and give the shopkeeper a written receipt so he is not left guessing what was taken.