This function encompasses having the jury see the case through the expert’s eyes. “My opinion is ..” type testimony is not sufficient. When the expert teaches the jury, they will see the case as the expert sees it and, assuming the jury is composed of reasonable people, they will make the same decision as the expert.
In local news coverage of many cases, LTC Alphin’s testimony style has been likened as “…professorial…”. This was specifically described not as talking down to the jury but helping the jury understand how and why something happened by teaching them how things work. This ability of LTC Alphin to educate a jury was key in instances such as the Dean case, where an innocent man walked free.