"I don’t see any evidence that there was criminal intent here," says Clif Burns, a lawyer at Crowell & Moring in Washington DC who specializes in national-security law, including export controls and trade sanctions.

[6] Soleimani had been invited by the Mayo Clinic in Minnesota to lead a research program; upon his arrival in the United States, he was arrested and transferred to a prison in Atlanta.

Professor Masoud Soleimani traveled to the US in autumn 2018, where he planned to complete the final stage of his research on treating stroke patients as a visiting scholar at the prestigious Mayo Clinic in Minnesota.

Now a principal scientist at the pharmaceutical firm AstraZeneca in Gaithersburg, Maryland, Ghaedi told Nature that she purchased the proteins in part because they are cheaper and more readily available in the United States than in Iran.

Eight months later, on 24 October 2018, a federal grand jury indicted all three scientists under seal — or behind closed doors — on two counts of conspiring to export goods to Iran without authorization.

"I don’t see any evidence that there was criminal intent here," says Clif Burns, a lawyer at Crowell & Moring in Washington DC who specializes in national-security law, including export controls and trade sanctions.