Did South Africa's curfew policy reduce COVID-19 cases? Evidence from December 2020.

> What impact did South Africa’s nationwide curfew of December 2020 have on COVID-19 cases? The evidence, based on daily case data, shows a sharp and immediate decline in infections following the curfew’s implementation. The findings highlight the value of targeted restrictions, particularly when combined with alcohol bans, and offer policy lessons on timing, communication, and equity in designing effective public health interventions. Introduction   When South Africa faced a sharp surge in COVID-19 cases during the pandemic’s second wave in late December 2020, the government moved swiftly to impose a nationwide nighttime curfew. Starting on 29 December, movement was prohibited between 9pm and 6am. The rationale was straightforward: reduce late-night gatherings, especially those linked to alcohol consumption, and thereby cut opportunities for the virus to spread. But did the curfew actually work? Public debates at the time were divided. Some argued that it was a blunt instrument that punished millions who posed little risk, while others believed that curfews offered a crucial, targeted alternative to harsher full-scale lockdowns. Until recently, there was little rigorous evidence to settle this debate in the South African context. What the data shows   Using daily COVID-19 case data from early 2020 to the end of 2021, I examined whether the December 2020 curfew had a measurable effect on infections. The analysis employs a  R egression  D iscontinuity D esign (RDD), depicted in Figure 1 , focusing on the days immediately before and after the curfew was introduced. RDD is a way of studying policy effects by comparing outcomes just before and after a policy intervention date. This “natural experiment” provides a clean way to isolate the impact of the curfew from other factors, since the policy was imposed suddenly and uniformly across the country. Figure 1: R egression  Discontinuity   Source: Author’s own computation The results show a cl