Transcript for Signs show that special counsel is pursuing a possible obstruction of justice case
special counsel is seeking to interview the man who quit as spokesperson for the president's team? What did he see that he did not like? ABC's Pierre Thomas. Reporter: He was the spokesman for president trump's legal team. Good afternoon, everyone, I'm Mork reco mark Corallo. Reporter: An insider often called upon to give explanations. But tonight, ABC news is learning more details about what allegedly caused mark Corallo to abruptly leave the trump team. Something the special counsel apparently wants to talk to him about, as Robert Mueller aggressively pursues the possibility of obstruction of justice. Corallo quit in July, sources say, in part because he was concerned that some in president trump's camp were looking to unearth negative information about Mueller, in an effort to find potential conflicts of interest for Mueller, whose investigation the president has repeatedly called a witch hunt. The entire thing has been a witch hunt. Reporter: Corallo also resigned less than two weeks after news broke of that now-infamous trump tower meeting involving the president's son, don Jr., and a group of Russians. Mueller apparently wants to find out exactly what Corallo knows about don jr.'s initial misleading statement, which the president helped write from aboard air force one, saying that meeting was "Primarily about the adoption of Russian children." Days later, e-mails revealed don Jr. Agreed to meet the Russians because he had been promised dirt on Hillary Clinton by the Russian government. In retrospect, I probably would have done things a little differently. Reporter: Michael Wolff's new book portrays Corallo as troubled by the prident's involvement in crafting that first misleading statement. Wolff writing, "Corallo believed the meeting on air force one represented a likely obstruction of justice." Pierre Thomas and his team breaking this story tonight. And Pierre is with us. And you have reporting tonight that the special counsel reached out to Corallo's attorneys, in the last two weeks? Reporter: David, negotiations are under way for Mueller's team to interview Corallo. The likely topic, any concerns he had about obstruction of justice. Tonight, his attorney declined to comment, David.
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