(CNN) President Donald Trump's anger toward Robert Mueller's investigation has a new comrade -- an indicted Russian company.

The special counsel office's criminal case against Concord Management and Catering has gotten so heated that the Russian company's defense attorney Eric Dubelier told prosecutor Jeannie Rhee her presentation in court Wednesday was "bulls***."

Dubelier appeared to lose his temper as he approached Rhee moments after the judge left the courtroom. The brief outburst followed weeks of Dubelier indicating in court filings and hearings that he's ready to play hardball with Mueller's team and Rhee in particular.

During the hearing, Dubelier described a plan of attacking the prosecutors' case, which accuses Concord of funding a Russian operation to spread election propaganda on social media, from all angles. His team would challenge the constitutionality of the conspiracy charge Concord faces and would attack the authority of the special counsel's office both "generally and specifically," he said.

Former campaign chairman Paul Manafort, another defendant fighting a case against Mueller, previously tried to undercut the special counsel's authority. A federal judge in DC said Tuesday that Mueller had the authority to prosecute Manafort for his lobbying work years before the campaign, and Manafort still awaits a Virginia judge's decision.

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