The new punishment comes in response to the brutal gang rape and murder in April of a 14-year-old girl on her way home on the island of Sumatra.
Seven teenage boys were each sentenced to 10 years in prison for the crime, which prompted national outrage and revived previous calls for chemical castration as a punishment against child sex offenders.
Mr. Joko told a news conference at the presidential palace in Jakarta, the Indonesian capital, that he had signed a decree amending the country’s 2002 law on child protection to enable judges to hand down the punishment at their discretion.
“The inclusion of such an amendment will provide space for the judge to decide severe punishments as a deterrent effect on perpetrators,” Mr. Joko said.
“These crimes have undermined the development of children, and these crimes have disturbed our sense of peace, security and public order,” he said. “So, we will handle it in an extraordinary way.”
Mr. Joko said that “sexual violence against children has increased significantly” in Indonesia, although his government has not provided data to back his assertions. He also increased the jail sentences for child sex offenders to a maximum of 20 years from 10 years.
The local news media has cited the country’s National Commission on Violence Against Women as saying that around 35 Indonesian women a day are victims of sexual violence.
Through chemical castration, drugs are used to reduce a person’s sex drive. A number of countries have employed the punishment for convicted sex offenders and pedophiles, in many cases in exchange for more lenient prison sentences. They include Australia, Russia, South Korea and the United States.