Crimes Against Morality: Unintended Consequences of Criminalizing Sex Work

Criminalizing sex work in low-income settings like Indonesia decreases earnings of the female sex workers and increases the prevalence of STI infections.


Female sex work is more prevalent in lower income countries like Indonesia, and research suggests that sex work could be a key driver of the HIV epidemic. Amnesty International argues that decriminalization of sex work improves the safety and conditions of work environments for these women, for example, by improving their access to healthcare. However, there is little empirical evidence about the actual impact of regulating sex markets in lower income countries.

As is common in many countries, sex work in the Indonesian province of East Java occurs in both formal worksites (i.e., brothels) and informal worksites (i.e., the street). In November 2014, local officials in East Java unexpectedly criminalized sex work in one district, Malang. The new policy closed all formal sex worksites in the district, enforcing the policy through police raids and penalties. The local health ministry also stopped providing health exams and free condoms at formal worksites. However, the local sex market became more clandestine and continued to operate.

Researchers investigated the new policy’s impact on the sex market, the welfare of the sex workers, and the general population by collecting data from sex workers and their clients in Malang and neighboring districts before and after the policy change. Comparisons were made based on demographic data as well as key health and socioeconomic indicators, such as STI infections and weekly earnings.


Criminalization of sex work ultimately increased sexually transmitted infections among female sex workers and the general population, while decreasing the earnings of women who left sex work because of the new law.

  • Criminalizing sex work increased sexually transmitted infections (measured by biological tests) among female sex workers by 27.3 percentage points (by 58%) from  46% at baseline.
    • After criminalization, condom prices increased by 200% in criminalized areas, sex workers were more than 51.6 percentage points less likely to be able to produce a condom, and clients report a 61 percentage point decrease in condom sex.
  • Criminalization decreased the weekly earnings among women who left sex work due to criminalization and decreased their ability to earn enough to meet their daily needs and support their general well-being (54% of baseline sex workers in criminalized areas reported less than adequate earnings compared to 36% of baseline sex workers in non-criminalized areas).
    • Criminalization also decreased the women’s ability to meet their children's school expenses while increasing the likelihood that children begin working to supplement household income.

While criminalization may improve population STI outcomes if the market shrinks permanently, this study showed that at five years post-criminalization the market rebounded and likely increased STI infections, including HIV, in the general population. Thus, criminalization of sex work may be counterproductive by restricting organizational support of sex worker health and inhibiting sex workers’ ability to openly access support and health services.


The study is based on a natural experiment that encompasses the districts of Malang, Pasuruan, and Batu in East Java where formal (i.e., brothels) and informal (i.e., the street) sex work occurs. Seventeen worksites were included in the study: nine in Malang (six are formal and became criminalized) and eight were in the neighboring districts of Pasuruan and Batu (four of which were formal).

A census was conducted at four points in time capturing the total number of sex workers at every site: January–February 2014 (pre-criminalization), September 2014 (post-announcement but still pre-criminalization), February–March 2015 (post-criminalization), and in October 2019 (five years post-criminalization). Further baseline and end-line surveys of sex workers and clients collected information on demographics, employment and income, details of commercial sex transactions and characteristics of clients, HIV/STI knowledge, risk and time preferences. To eliminate reporting bias of STI symptoms, biological test results from vaginal swabs were collected.

The February–March 2014 baseline survey included 505 female sex workers identified at formal and informal worksites in the first census and 300 male clients across the worksites. The end-line May–June 2015 survey included follow-ups with sex workers interviewed previously and new sex workers at the worksites found during the February– March 2015 census and at the time of the end-line survey. A total of 198 women were still in sex work at end-line, 144 of whom were also surveyed at baseline and make up the main end-line sample used to analyze the impact of criminalization. Data from a new sample of 293 clients at end-line was also collected. Approximately 70 percent of baseline sex workers were located at end-line either in person, by phone, or via an informant regardless of whether they were still engaged in sex work. The 31 percent attrition rate is comparable to other surveys of highly mobile populations.A difference-in-differences framework was applied to the panel data collected from sex workers and repeated cross-section of clients in East Java at both criminalized and non- criminalized worksites, before the criminalization was anticipated and after the criminalization occurred.

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