Does the doctrine of 'opening the door' require the traditional Federal Rules of Evidence Rule 403 balancing of probative value versus prejudicial effect?

QUESTIONS PRESENTED 1. Does the doctrine of “opening the door” require the traditional Federal Rules of Evidence Rule 403 balancing of probative value versus prejudicial effect? 2. Should District Courts be permitted to refuse a request for an instruction for the jury to disregard a prohibited murder accusation against a Plaintiff? 3. Does the Eighth Circuit persist in failing to credit Plaintiffs with favorable facts at the summary judgment phase?