MANILA, Philippines — Singapore has executed its first woman in nearly two decades for drug trafficking, amid protests from anti-death penalty advocates that say the punishment doesn't deter the use or availability of drugs.

Saridewi Binte Djamani, 45, was hanged Friday after being convicted in 2018 of possessing "not less than 30.72" grams of heroin, according to Singapore's Central Narcotics Bureau.

"The Misuse of Drugs Act provides for the death penalty if the amount of diamorphine trafficked is more than 15 grammes," the bureau said in a statement. "Thirty-point-seventy-two grammes of diamorphine is more than twice that amount, and is sufficient to feed the addiction of about 370 abusers for a week."

Despite an appeal and an attempt to get a presidential pardon, Djamani's punishment was imposed – making her the first woman to be executed in Singapore since Yen May Woen in 2004, also convicted on drug charges.

Singapore argues that its harsh laws help deter drug offenses in the city-state, but anti-death penalty advocates disagree.

Phil Robertson, deputy Asia director of Human Rights Watch, called Singapore's policies inhumane and its drug law draconian.

"The execution of Saridewi Djamani, the first woman in decades to go to the gallows, shows that this galloping effort to show the government is tough on drugs will spare no one," he said in a statement emailed to reporters. "The death penalty is an inherently cruel and unusual punishment that should be applied to no one, yet Singapore seems to positively relish these cases to demonstrate how hard they are on drugs."

Amnesty International's Chiara Sangiorgio said in a statement ahead of Djamani's execution that "there is no evidence that the death penalty has a unique deterrent effect or that it has any impact on the use and availability of drugs."

"The only message that these executions send is that the government of Singapore is willing to once again defy international safeguards on the use of the death penalty," he said.

A 2019 study that examined whether the effectiveness of the death penalty in deterring drug crime in the Philippines — a country that has recently debated whether to reinstate it for drug convictions — found that punishment does not deter crime. Use of the death penalty was frequently excessive for the crime committed, the study's authors said, and disproportionately affected lower-income defendants.

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