Effectiveness of Penalties for Lockdown Violations During the COVID-19 Pandemic in Germany.

To investigate whether the imposition of fines can mitigate the spread of COVID-19. We used quasi-experimental difference-in-difference models. On March 20, 2020, Bavaria introduced fines as high as €25 000 (US $28 186) against citizens in violation of the (federal state's) lockdown policy. Its neighboring (federal states), on the other hand, were slow to impose such clear restrictions. By comparing 38 (counties) alongside Bavaria's border from March 15 to May 11 using data from the Robert Koch Institute, we produced for each its (1) time-dependent reproduction numbers () and (2) growth rates in confirmed cases. The demographics of the were similar enough to allow for difference-in-difference analyses. that introduced fines on March 20 reduced the by a further 0.32 (95% confidence interval [CI] = -0.46, -0.18;  < .001) and decreased the growth rate in confirmed cases by an additional 6 percentage points (95% CI = -0.11, -0.02;  = .005) compared with the control group. Imposing fines may slow down the spread of COVID-19. Lockdowns may work better when governments introduce penalties against those who ignore them.