Car keys are among the most ordinary things in a household, often within everyone’s reach. But when an underage child takes the family car and kills someone, parents may escape criminal liability by proving they were unaware of the offence, even if reasonable precautions could have prevented it. Section 199A of the Motor Vehicles Act allows ignorance to serve as a defence independent of due diligence.

A recent fatal crash in Kochi brings this distinction into focus. A 17-year-old allegedly driving his father’s Mercedes-Benz killed a roadside eatery owner. His father, an Additional District Judge, maintains that he was asleep when his son took the car. Whether he bears criminal responsibility is for the courts to decide.…