In the months that followed, he fumed in online postings about the racism he felt as a black man - from his former employer, from the police, from a white woman he dated.
And he appeared to dabble with a run for mayor in his hometown of St. Louis, Missouri, but failed to attract more than a single $25 donation in an online fundraising effort to get on the ballot.
"The white New York liberal media makes me vomit with their arrogant, patronizing, bigotry," Thompson, 31, wrote in an essay he posted online on July 7, 2016.
In a 5,000-word account he described a racist smear campaign by the Intercept. He wrote that the outlet, which describes itself as focusing on adversarial journalism, was "the token negro whisperer."
The Intercept initially was launched as a platform to report on the documents released by former security contractor Edward Snowden.
"I now have a Korean sense of Han — unadulterated rage against bigoted bullies, in this case the white liberal media," he wrote. "It's no wonder these places have so few black faces."
Five months before his July 2016 post, Betsy Reed, the Intercept's editor in chief, had published an apology to readers for "a pattern of deception" in Thompson's work. He had made up quotes and impersonated people, including Reed herself, using fake Gmail (GOOGL.O) accounts.
Reed's accusation would foreshadow a criminal complaint unsealed on Friday in New York. Prosecutors said Thompson impersonated a girlfriend who had dumped him to email threats to several Jewish organizations around the country.
The ex-girlfriend was white, as Thompson underscored in a frenzy of messages on his Twitter account in the days leading up to his arrest on Friday morning.
She is an "awful white woman" he wrote in a typical post, in this case directed at the U.S. Secret Service, the agency that protects the U.S. president.
She is a "disgusting nasty racist white woman," read another post in which he said she had threatened to kill President Donald Trump.
"I'm being stalked and harassed by a white nasty white woman," he wrote in a third. The ex-girlfriend could not be reached for comment.
The couple broke up a few weeks after he published his essay in July, according to the criminal complaint. At some point he moved back to St. Louis, far from the Intercept's "fancy New York office (with free beer no less)" where he had briefly felt the beginnings of success, according to his essay.
On Nov. 15, 2016 he posted a manifesto on a fundraising website describing his bid for mayor to "fight back against Trumpian fascism and socio-economic terrorism."
His 10-point platform touched on themes from his work at the Intercept: police brutality against black people, the homeless and the poor.
Meantime, he worked as communications director at the Gateway Housing Foundation, according to an online profile. The small St. Louis non-profit, which helps the homeless, could not be reached for comment.
"Now of course I'm not perfect," Thompson wrote in the mayoral manifesto he hoped would launch a new career. "I've made mistakes. We all have."
Banner and thumbnail credit: Reuters, Jim Young