The Jewellery Shop Theft: Testing Three Alibis
A jewellery shop in Mysuru reports a theft of 320 grams of gold at 9:00 a.m. The shop closed at 8:00 p.m. the previous day. The constable reviews the entry register and CCTV. Three employees were present after closing: Ravi, the manager; Sana, the cashier; and Deepak, the security guard. The main-door camera shows Ravi leaving at 8:45 p.m. and Sana leaving at 9:10 p.m.; the guard's cabin camera stops recording at 9:00 p.m. The alarm log shows the alarm was disabled at 8:55 p.m. and re-enabled at 9:25 p.m. Ravi says he went straight home, 6 km away, and reached at 9:00 p.m.; he produces a cab receipt timed 8:50 p.m. Sana says she left at 9:10 p.m. and walked 500 m to her sister's house, arriving at 9:15 p.m. Deepak says he was on his rounds and did not enter the shop. The back door was found unlocked.
1. Using the timeline, identify the inconsistencies in the statements and rank the three employees as persons of interest.
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The critical window is 8:55 p.m. to 9:25 p.m., when the alarm was disabled. Whoever disabled it was almost certainly inside the shop at 8:55 p.m.
Ravi left at 8:45 p.m., ten minutes before the alarm was disabled. His cab receipt is timed 8:50 p.m. A 6 km trip in 10 minutes would require an average of 36 km/h, which is possible on city roads at night, but the receipt only proves he boarded a cab; it does not prove he stayed away. He is the weakest candidate but not eliminated.
Sana was inside until 9:10 p.m., so she could have disabled the alarm at 8:55 p.m. But the alarm was re-enabled at 9:25 p.m., fifteen minutes after she left, so she would have needed an accomplice or a return visit. Her walk of 500 m in 5 minutes is 6 km/h, which is brisk but plausible.
Deepak was on duty throughout, his cabin camera stopped at 9:00 p.m., the alarm was disabled at 8:55 p.m. and re-enabled at 9:25 p.m., and the back door was unlocked. He had the opportunity, access, and duty to monitor the alarm. He should be ranked first, Sana second, Ravi third.
2. What records and physical evidence should the constable collect to test each alibi?
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For Ravi: the original cab receipt, the cab's GPS or trip log, the driver's statement, and any CCTV on the route or at his home. The purpose is to establish the drop time and whether he returned to the shop.
For Sana: a statement from her sister, any CCTV on the 500 m route, and the exact time she was seen leaving the shop. The purpose is to test whether she could have doubled back.
For Deepak: the duty roster, the guard's tour book, the key register, the alarm panel for fingerprints, the DVR and its recording settings, the back door and lock for fingerprints and tool marks, and the shop's stock register. The constable should also seize the DVR to preserve the footage and check why the cabin camera stopped at 9:00 p.m.
3. If the cab receipt is genuine, does it clear Ravi? Explain.
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No. A genuine receipt proves only that Ravi boarded a cab at about 8:50 p.m. It does not prove he reached home, stayed home, or did not return. He could have taken the cab part of the way, returned by another vehicle, or had an accomplice inside the shop.
The timeline does make him less likely to be the person who disabled the alarm at 8:55 p.m., because a 6 km trip in five minutes is implausible even at night. But the re-enabling at 9:25 p.m. and the unlocked back door mean the constable must still verify the cab's GPS trail, the drop time, and any later movement. The receipt narrows the window but does not establish innocence.