For 15 years prior he was a producer for ABC News and Peter Jennings Productions.
He began that tenure as an associate producer for ABC News investigative correspondent Brian Ross and for the newsmagazine Day One.
Summa's documentaries for Peter Jennings Reporting include Peter Jennings' last documentary, Breakdown: America's Health Insurance Crisis, which revealed the dangers of rising health care costs, as well as From the Tobacco Files, exposing failures of the public health community; How To Get Fat Without Really Trying, examining how agriculture policies and excessive marketing to children contribute to obesity; Bitter Medicine: Pills, Profit and the Public Health, an investigation of the pharmaceutical industry; The Gunfight, an exclusive look inside the National Rifle Association of America; and Never Say Die: How the Tobacco Industry Keeps on Winning, an investigation of the tobacco industry's political tactics.
His investigative reporting on tobacco, health care and firearms also appeared on World News Tonight, Good Morning America, and Nightline.
His reporting on the tobacco industry was chronicled in the book Civil Warriors by Dan Zegart.