"Nathaniel Persily at Stanford University Law School said one relevant statute is the Bipartisan Campaign Reform Act of 2002.
"A foreign national spending money to influence a federal election can be a crime," Persily said. "And if a U.S. citizen coordinates, conspires or assists in that spending, then it could be a crime."
Persily pointed to a 2011 U.S. District Court ruling based on the 2002 law. The judges said that the law bans foreign nationals "from making expenditures to expressly advocate the election or defeat of a political candidate."
Another election law specialist, John Coates at Harvard University Law School, said if Russians aimed to shape the outcome of the presidential election, that would meet the definition of an expenditure.
"The related funds could also be viewed as an illegal contribution to any candidate who coordinates (colludes) with the foreign speaker," Coates said.
To be sure, no one is saying that coordination took place. What’s in doubt is whether the word "collusion" is as pivotal as Jarrett makes it out to be.
Coates said discussions between a campaign and a foreigner could violate the law against fraud.
"Under that statute, it is a federal crime to conspire with anyone, including a foreign government, to ‘deprive another of the intangible right of honest services,’ " Coates said. "That would include fixing a fraudulent election, in my view, within the plain meaning of the statute."
Josh Douglas at the University of Kentucky Law School offered two other possible relevant statutes.
"Collusion in a federal election with a foreign entity could potentially fall under other crimes, such as against public corruption," Douglas said. "There's also a general anti-coercion federal election law."
In sum, legal experts mentioned four criminal laws that might have been broken. The key is not whether those statutes use the word collusion, but whether the activities of the Russians and Trump associates went beyond permissible acts."