An apology is not enough for Guatemalans deliberately infected with syphilis by a US medical team in the 1940s. Five months after the American taxpayer-funded medical experiment came to light, victims have brought a class-action lawsuit against the US government seeking compensation for resulting health problems.

Seven named plaintiffs, which include both victims and heirs living in Guatemala, filed the lawsuit Monday in a Washington, D.C., district court on behalf of 700 Guatemalan soldiers, mental health patients, and orphans. The victims were all secretly experimented on from 1946 to 1948, the complaint says.

The experiments were “both unprecedented and unequivocally impermissible in the United States and throughout the civilized world,” the complaint states.

The court brief charges that US public health doctors hired prostitutes diagnosed with syphilis or gonorrhea to have sexual relations with soldiers, prison inmates, and psychiatric patients in Guatemala with the intention of spreading the disease. Once the unknowing subjects were diagnosed with illnesses, the US medical team tested them for potential cures, including penicillin. Orphaned Guatemalan children as young as 6 years old were used as an uninfected test group, according to the suit.

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The US government apologized to Guatemala in October when the six-decade-old project was first revealed in a policy journal, calling the experiments “clearly unethical” and condemning the “appalling violations” of medical ethics and human decency. Both the US and Guatemalan governments announced investigations into the case.

But when victims’ lawyers contacted the Department of Justice to negotiate a solution last week, they received no reply, say the attorneys of Florida-based Conrad & Scherer and New York-based Parker Waichman Alonso.

The Justice Department said the government will review the complaint to determine how it will respond. Spokesman Charles Miller said he could not say whether his office had discussed a settlement with the plaintiffs' lawyers since the matter is now in litigation. The US Department of Health and Human Services, the main defendant named in the case, did not comment.

The complaint compares the victims to those of the 1930s Tuskegee syphilis experiments in Alabama, where hundreds of poor African Americans were observed for decades without being told they had the disease. The same Public Health Service doctors from the Tuskegee case had even initially supervised the Guatemalan experiments, according to Piper Hendricks of Conrad & Scherer.

The lawsuit demands punitive damages to be decided by the court. While damages are hard to predict, Ms. Hendricks says juries have granted large awards in similar Alien Tort Statute cases, where human rights violations were committed by US citizens in a foreign country. She pointed to the 2010 “Chuckie Taylor” case, where a US citizen charged with torture in Liberia was found liable for over $20 million in damages.

Hendricks acknowledged, however, that US judges have grown reluctant to take on class actions. She says she’ll have to show strong similarities among victims of the class, many of whom she hopes will join the suit now that it has been filed.

“If there was any question, which I don’t think there was, as to whether nonconsensual human medical experimentation was acceptable, [the] Nuremberg [Trials] answered that loud and clear. And here we were across the ocean continuing this type of experimentation,” says Hendricks.