IDFC Institute's Safety Trends and Reporting of Crime (SATARC) Survey results are quoted in this Livemint piece to get a better sense of the underreporting of crime in Delhi, which tells the story behind the official crime figures put forward by the National Crime Records Bureau (NCRB).
"To be sure, official crime statistics suffer from an under-reporting bias and this may vary from state to state depending on the nature of the crimes. Therefore it also makes sense to gauge the extent of under-reporting through independent surveys...
...One recent large-scale survey by the IDFC Institute, which polled people across major Indian cities, found that there was widespread under-reporting of crime across the four cities surveyed: Delhi, Mumbai, Chennai and Bengaluru. But Delhi, in particular, had the worst record when it came to registering first information reports (FIRs)."
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