Peltzman Effect

The Peltzman Effect, named after economist Sam Peltzman, is the observation that safety measures often fail to reduce total harm because people compensate for increased safety by taking greater risks. When seatbelt laws were introduced, drivers drove more aggressively — offsetting some of the safety gains. When helmets were mandated for cyclists, some cyclists rode more recklessly. The mechanism is intuitive: when you feel safer, your risk tolerance increases, and you adjust your behaviour to consume the safety margin that the new measure created. In business, the Peltzman Effect operates wherever safeguards exist. Companies with large cash reserves take bigger strategic bets. Teams with robust testing infrastructure ship less carefully. Founders with generous investor backing experiment more recklessly. The effect doesn't mean safety measures are useless — it means their benefits are partially consumed by the increased risk-taking they enable, and the net impact is always less than the gross impact.

When implementing any safety measure, anticipate that people will compensate by increasing risk. Design safeguards that are invisible to the risk-taker or that don't change the perceived risk profile. Alternatively, pair safety measures with accountability structures that prevent the safety margin from being consumed. The question isn't "does this safety measure work in isolation?" but "how will behaviour change once people know the safety measure exists?"

The Peltzman Effect holds that safety measures often fail to achieve their full intended benefit because people compensate by taking greater risks. In business, it operates wherever safeguards exist — financial reserves, testing infrastructure, insurance, and fallback plans all tend to increase risk-taking rather than simply reduce harm. Counter it by designing safeguards that don't signal increased safety margins to risk-takers.