Levinson was reportedly on an independent investigation, possibly an unofficial mission to recruit a CIA asset, when he went missing on Kish Island in March 2007. A fellow American, Dawud Salahuddin, reported being briefly detained with Levinson by Iranian authorities, and the country’s state media later acknowledged the incident, although Tehran has subsequently denied any knowledge of Levinson’s whereabouts or the circumstances of his disappearance.

The Press TV report that initially boasted of Levinson’s detention was one of the pieces of evidence cited in filing the lawsuit around the time of the 10th anniversary of his disappearance. Voice of America News also quoted a lawyer for Levinson’s family as saying that Iranian figures with knowledge of the case have leaked information confirming that Levinson remained in Iranian custody for years after the arrest.

Some have speculated that Levinson died while in detention, but his family has seen no evidence to convince them of this conclusion. CNN points out, however, that their lawsuit does point out that Levinson has likely been subject to physical and psychological torture during the intervening 10 years, since these tactics are frequently used in the questioning and punishment of Iranian prisoners, especially political prisoners.

At one point, Iranian authorities attempted to exploit speculation about Levinson’s death by claiming to possess information to suggest that he had been taken to Pakistan by non-state actors, and that he had died and been buried at a specified location. But investigations into that location turned up no remains or other evidence of his having been there. If still alive today, Levinson would be 69 years old.

His advocates had been briefly hopeful that Levinson would be released or that his location and condition would be revealed around the time of the implementation of the Iran nuclear agreement in January of last year. That implementation coincided with the release of four other Americans who had been taken prisoner for dubious reasons in recent years, but Levinson’s family discovered only after their release that his case had not been resolved along with these others.

The incident led to considerable criticism of the Obama administration’s handling of Iranian affairs. VOA News indicates that some of Levinson’s advocates continue to believe that he is being kept as a hostage in Iran, to be used as a bargaining chip in hopes of gaining more concessions like those that led to President Obama’s successor declaring the nuclear agreement “the worst deal ever negotiated.”

This highly critical voice has seemingly encouraged Levinson’s family and other victims of the Iranian regime to latch onto the administration of President Donald Trump as a source of hope for more assertive action on these sorts of cases. Indeed, VOA News reports that Robert Levinson’s son Daniel had met with the administration personally and urged it to “constantly annoy” Iran until significant information is released.

Meanwhile, CNN quoted Robert Levinson’s daughter Stephanie Curry as saying, “We are very confident that President Trump has the deal-making skills that are necessary in order to bring him home and to take a stronger stance with Iran and demand his release.”

Shortly after the announcement of the lawsuit, to which Iran has given no public response, it was reported that the Trump administration and two congressional committees had announced plans for new sanctions on the Islamic Republic, leaving the nuclear agreement in place but more aggressively targeting the country over its ballistic missile activities and support for international terrorism.