The parents of Seth Rich - the Democratic National Committee staffer police believe was murdered during a botched robbery in 2016 - have sued Fox News over a retracted story that peddled a conspiracy theory about his murder, claiming the network "intentionally exploited" the tragedy for political purposes.The May 2017 story stated, falsely, that investigators had evidence showing Rich leaked thousands of DNC emails to WikiLeaks in the midst of the 2016 presidential election, just weeks before he was shot to death in Washington. That story line - popular among conspiracy theorists and in alt-right online groups - contradicts U.S. intelligence that Russia was behind the WikiLeaks email dump that damaged Hillary Clintonís campaign.Foxís story fell apart quickly after the FBI pointed out that a "federal investigator" and "FBI report" referenced in the story as sources did not exist. The second core source in the story, private investigator and Fox contributor Rod Wheeler, claimed the Fox reporter fabricated his quote saying he had evidence of emails between Rich and WikiLeaks. He has since sued the network for defamation. (Fox News has denied all his claims.)Read More: Floridaís 2018 Legislature was the least productive in two decadesFox News retracted the story six days after it was published, saying the story "was not initially subjected to the high degree of editorial scrutiny we require for all our reporting."But Joel and Mary Rich say that the story has followed them ever since, wreaking irreversible damage on them and their son, whose legacy has become entangled in a conspiracy theory that Fox elevated "from the fringe to the front pages and screens of the mainstream media," the lawsuit says. The couple is seeking unspecified damages for emotional distress."No parent should ever have to live through what we have been forced to endure," Joel and Mary Rich said in a statement released through their media representative. "The pain and anguish that comes from seeing your murdered sonís life and legacy treated as a mere political football is beyond comprehension."A spokeswoman for Fox News declined to comment due to pending litigation. Another defendant, Malia Zimmerman, the reporter on the retracted Fox story, could not be immediately reached for comment. Ed Butowsky, a Dallas businessman and a Fox guest who allegedly built the story behind the scenes, was also sued. Asked about evidence for the storyís claims, he said "thereís a lot out there," but offered no facts.The lawsuit describes months of strategic planning among Zimmerman, Butowsky and Wheeler to convince the Riches that evidence linked Seth Rich to the DNC leaks. The political motivation behind the story, the suit alleges, was to absolve the Trump administration of the investigation into Russian collusion by showing that the hacking instead came from within - from 27-year-old Creighton University graduate Seth Rich.Zimmerman and Butowsky first reached out to the Riches in January 2017, under what the suit describes as false pretenses as they offered to help get to the bottom of Sethís death. The Riches say in the lawsuit that Butowsky convinced them to accept Wheelerís help as a private investigator after assuring them that Wheeler would share his findings only with them.It all turned out to be a lie, the suit claims.By April, Wheeler and Butowsky met with then-White House press secretary Sean Spicer about the Fox story - without Mary and Joel Richís knowledge, they say.Speculation that the White House had any role in the retracted Fox story exploded after Wheeler filed his defamation lawsuit against Fox in August 2017. In it, he cited a text message in which Butowsky tells him that he let President Donald Trump review a draft of Zimmermanís story and that the president wanted it published "immediately." (Butowsky has maintained that was just a joke.) Spicer has confirmed that he met with Wheeler and Butowsky, but said the story "had nothing to do with advancing the presidentís domestic agenda - and there was no agenda."Both lawsuits, however, point to other messages from Butowsky that they say make clear his and Foxís political motivations. On the day the story was published, he allegedly wrote to Wheeler, "If you can, try to highlight this puts the Russian hacking story to rest." He also allegedly wrote to various Fox producers saying, "One of the big conclusions we need to draw from this is that the Russians did not hack our computer systems and steal emails and there was no collusion like trump with the Russians [sic]," according to emails cited in the lawsuit.The story, published May 16, went viral. A tape recording of a three-way call with Zimmerman, Wheeler and Butowsky that NPR has verified showed Zimmerman conceding that Wheeler never said "my investigation up to this point shows there was some degree of email exchange between Seth Rich and WikiLeaks," but that her bosses told her to keep his quotes in the story.Mary and Joel Rich said in the lawsuit that, nearly a year later, they still canít stop reading the comments and articles and blogs and even tweets defaming their son and invoking the conspiracy. "Joel and Mary feel that in order to protect and defend their son against attacks on his character, they must read and understand what is being said about him, which is overwhelming," the suit says.The suit claims the couple has developed post-traumatic stress disorder and anxiety, among other afflictions, as a result of the viral conspiracy theory about Seth."Imagine that every single day, with every phone call you hope that itís the police, calling to tell you that there has been a break in the case," they said in a statement in the lawsuit. "Imagine that instead, every call that comes in is a reporter asking what you think of a series of lies or conspiracies about the death. That nightmare is what our family goes through every day."The suit says Fox News never apologized to Joel and Mary Rich for the retracted story about their son.