There are three truths about expert testimony.

The first, which first-time jurors discover to their dismay: expert testimony isn’t like what they see on their favorite TV legal dramas. Real testimony is long—running hours to days—and filled with complex jargon and mind-numbing data that turns into white noise when delivered by the wrong witness.

The second truth, which dismays attorneys and their clients: expert testimony is expensive, costing thousands of dollars a day at trial and up to seven figures over the course of a long, complex case.

But the third truth is the most critical: expert testimony is the pivot on which many trials turn.

During closings of Ina Ahrens's trial against cigarette makers R.J. Reynolds and Philip Morris. Gary Paige tells jurors the Heaviness of Smoking Index shows Karl Ahrens was addicted to nicotine.

Updated 2/12/16, 2:04 p.m.:

St. Petersburg, FL—Jurors today awarded $9 million in compensatory damages to the widow and son of a Florida man after finding the nation’s two largest tobacco companies responsible for his fatal lung cancer. Ahrens v. Philip Morris and R.J. Reynolds, 07-013535-CI-08.

Decatur, GA—Trial is scheduled to begin next week in a suit by a man who claims a Conyers hospital’s medical staff failed to properly treat his wife’s aneurysm in time to prevent a series of strokes that caused her life-long brain damage. Evans v. Sutton, et al, 13A48465-4.

Dr. Allan Goldman tells jurors he is "sure" Elizabeth Smith had lung cancer before November 21, 1996, the bar date for her claim against two tobacco companies and more than a year before doctors diagnosed her with the disease. 

West Palm Beach, FL—A pulmonologist told jurors Friday he was certain a Florida smoker had lung cancer within the time frame allowed to bring her claim against two tobacco companies, and which closed more than a year before doctors diagnosed her with the disease. Smith v. R.J. Reynolds Tobacco Co., et al., 2007-CA-023930.

The trial: Mary Fellers v. Just People Inc.

The turning point: A security video showing Hunter Fellers, a mentally disabled adult who suffered from seizures, underwater for six minutes at an unsupervised pool party organized by Just People Inc., an organization that assists people with mental disabilities.

The result: A $2.022 million verdict for the plaintiff, Mary Fellers.