A sudden, local ban on sex work in one East Java district—unexpectedly imposed by local officials while neighboring districts stayed legal—creates a natural experiment to assess health and economic consequences. Data collected from female sex workers and their clients both before and after the policy change reveal substantial unintended harms.

📊 A Rare Natural Experiment in One East Java District

• Biological and survey data were collected from female sex workers and their clients before and after the district-level criminalization.
• The timing and geographic limit of the ban (one district versus adjacent districts) provide plausibly exogenous variation for causal inference.

🧪 What Was Measured and How

• Sexually transmitted infections (STIs) among female sex workers were measured using biological tests.
• Behavioral measures include condom access and reported condom use.
• Economic outcomes tracked include earnings for women who left sex work, household ability to pay children’s school expenses, and child labor within affected households.

📈 Key Findings

• STI Prevalence: Criminalization increased STIs among female sex workers by 58 percent (biologically measured).
• Mechanism: The STI increase was driven by reduced condom access and lower condom use after criminalization.
• Economic Harm: Women who left sex work because of criminalization experienced decreased earnings.
• Family Impact: Households showed reduced ability to meet children’s school expenses and an increased likelihood that children began working to supplement household income.

🔎 Longer-Term Outlook and Population Effects

• Short-term contraction of the market could, in theory, improve population STI outcomes if the market stayed permanently small.
• Empirical follow-up shows the market rebounded within five years after criminalization.
• Given the rebound, the probability of STI transmission in the general population is likely to have increased rather than decreased.

💡 Why It Matters

• Criminalizing sex work produced clear, measurable public-health harms and household-level economic setbacks in this case.
• Policy consequences extended beyond the targeted market, affecting children’s welfare and likely raising STI risk in the broader population once the market recovered.