(CNN) President Donald Trump's associates are looking to special counsel Robert Mueller for help in fending off a lawsuit from the Democratic National Committee over Russian influence in the last presidential election.

Jared Kushner, Roger Stone and Trump's Russia-connected real estate contacts have pointed to Mueller's lack of a conspiracy case regarding the Trump campaign and the Russian government as they defend against the lawsuit, which has already outlasted the Mueller probe.

Even with Mueller's investigation over, however, the lawsuit could keep questions of Trump's connections to Russia lingering in the court system.

Mueller did not find evidence to charge any Americans with conspiring with the Russians, though prosecutors have alleged that Russian government actors broke US law as they attempted to help Trump in the election. In the Mueller report, the special counsel found many times when Trump associates had been in touch with Russians in 2016, and documented how Trump campaign officials had realized that Trump could benefit from the Russians' efforts.

Mueller also noted in his report that he couldn't get to the bottom of some questions he had examined -- after being stymied by missing evidence or absent witnesses, hearing false statements from key target Paul Manafort and receiving contradictory stories from witnesses.

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