No error in trial court's refusal to allow questioning of an expert on a line of inquiry that had been established by another witness.
In a diversity action, federal law governs the review of counsel statements in closing arguments.
Given curative instruction, deft counsel's mis-characterization of the burden of proof was not plainly injurious.
http://media.ca8.uscourts.gov/opndir/18/06/172228P.pdf
Since 2011. An occasional commonplacing of the U.S. Circuit Courts of Appeal.
Neither an authoritative statement of the law nor legal advice. Quick work.