Two years after the Justice Department labeled him a Chinese spy only to abruptly withdraw that claim without explanation or apology, Temple University physics professor Xiaoxing Xi is suing the FBI agents who built the case against him.
In a suit filed Wednesday in federal court in Philadelphia, Xi alleges that U.S. counterintelligence investigators targeted him because of his ethnicity and willfully misinterpreted evidence to fit a false narrative that he stole secrets from a U.S. company.
His claims are likely to restoke debate about recent high-profile prosecutions of Chinese American scientists, which some critics have likened to the Cold War Red scares, and bring to a head Xi's icy standoff with agents and prosecutors in Philadelphia, who have repeatedly expressed reservations about absolving him.
They have never explained their decision in 2015 to drop their case before trial or discussed the evidence that prompted them to charge him.
The suit is believed to be the first brought by a Chinese American scientist against federal investigators since the government paid $895,000 in 2006 to settle claims by nuclear scientist Wen Ho Lee, who was fired from his job at Los Alamos National Laboratory amid ultimately unproven government allegations that he was spying for China.
"The fact that Professor Xi was charged on faulty information is deeply, deeply troubling," said his lawyer, Jonathan Feinberg. "The reason that we brought the lawsuit was to hold those who were responsible for those false charges responsible and to get information for him and his family about what prompted this investigation in the first place."
Xi, a naturalized U.S. citizen and world-renowned expert on superconductivity, resumed his position at Temple in September 2015, four months after federal prosecutors charged him with multiple counts of wire fraud.
But he remains plagued by concern that he and his family are still under surveillance and that his otherwise innocent actions may be misinterpreted as nefarious by colleagues, students, and the government.
"We cannot get rid of the thought that the FBI is reading every one of our emails and listening to our phone conversations," Xi, 59, said last year. "I am determined to move on, but that's there."
Prosecutors had alleged that Xi sent schematics for a sophisticated piece of equipment known as a "pocket heater" to a colleague in China, despite a pledge he signed to keep its design a secret. They also accused him of offering to build a world-class laboratory in China in return for lucrative appointments there.
Xi's criminal lawyers said that after meeting with a scientific expert hired by the defense, government officials realized that they had fundamentally misunderstood the science behind their case and the device schematics that they accused Xi of stealing had been readily circulated among the scientific community for years.
But Feinberg and co-counsel David Rudovsky and Susan M. Lin went further in their suit Wednesday, claiming agents knew even before charging Xi that their claims about the technology were faulty.
Their client first learned of the FBI's interest in his work, they said, when agents clad in bulletproof vests and armed with guns and a small battering ram burst into his Penn Valley home just after 6 a.m. on May 21, 2015.
They handcuffed him, drove him to a Philadelphia office, and strip-searched him before he was told why he had been placed under arrest, according to the lawsuit.
The case came at a particularly bad time for Xi, who says he had been offered the opportunity to chair the university's physics department just two days before his arrest. By the time he was allowed to return to campus, the position had been filled by a colleague. University officials have disputed that plans for Xi's chairmanship were ever concrete.
The collapse of Xi's prosecution four months later came on the heels of three other high-profile Justice Department missteps involving charges filed against Chinese American scientists, including a case prosecutors withdrew in 2014 against Sherry Chen, an Ohio-based hydrologist for the National Weather Service, who was accused of illegally accessing a government database and lying about a meeting with a high-ranking Chinese official.
While avoiding direct comments on any of those cases, the U.S. Justice Department has accused Chinese spy agencies of encouraging their nation's businesses to steal trade secrets from American corporations. Prosecutors here have wrung convictions against scientists and businessmen who attempted to pilfer everything from fighter-jet schematics to the details on how to make the pigment used to whiten Oreo cookie stuffing.
But the string of blunders prompted the Congressional Asian American Pacific Caucus and the Committee of 100, a group of influential Chinese Americans founded by the architect I.M. Pei and the cellist Yo-Yo Ma, to call on then-Attorney General Loretta Lynch to reexamine the department's approach to such investigations.
Xi's lawsuit seeks unspecified damages on claims of malicious prosecution, due process violations and unlawful searches and seizures. It specifically names only Andrew Haugen, a Philadelphia-based FBI agent assigned to Chinese counterintelligence who was the lead agent on the investigation, as a defendant.
But Feinberg, Xi's lawyer, said Wednesday that he anticipates filing further claims against Justice Department officials.
A spokeswoman for the FBI's Philadelphia field office declined to comment on the suit.