Rather than torture prisoners to unearth information, former U.S. Army Staff Sgt. Eric Maddox used detective work and psychological leverage to persuade his interrogation subjects to spill their secrets — the biggest of which was the hiding place of former Iraqi dictator Saddam Hussein.

That information, which led to the discovery and arrest of the ousted president, was surrendered by Saddam’s bodyguard after previous interrogations led to the capture of 40 insurgent family members, and yielded the location of the bodyguard’s wife and infant son.

“I made a straight-up deal with him: ‘You give me Saddam and those 40 walk,’ ” said Mr. Maddox, who was the keynote speaker at a fundraiser on Wednesday at Soldiers & Sailors Memorial Hall & Museum for Operation StrongVet Western Pennsylvania.

The Wexford nonprofit provides services including health care, counseling, housing help, legal assistance, education and job training for local veterans.

Unlike most Army interrogators, who complete an average of 200 interrogations during a single one-year tour, Mr. Maddox said in an interview Wednesday that he completed approximately 2,700 interrogations during his military service in eight deployments in Iraq, Afghanistan, South America, Southeast Asia and Europe from July 2003 to July 2014.

An Oklahoma native, Mr. Maddox began his military career as an infantry paratrooper for the 82nd Airborne Division and ultimately became the first civilian interrogator to work for former Defense Department Secretary Donald Rumsfeld. He was awarded the Bronze Star, the Legion of Honor and the National Intelligence Medal of Achievement, among other commendations.

His experience, along with a technique that focuses on identifying and meeting prisoners’ needs in exchange for information rather than punishing them for silence, contributed to a success rate of persuading 65 percent of prisoners to yield information, compared to the Army average of 4 percent, Mr. Maddox said.

“We’re not going to punish — we’re going to negotiate, compromise and cut deals, because that’s how you get intelligence,” he said.

In the hunt for Saddam, who fled Baghdad just before the city fell to U.S. forces in April 2003, that intelligence unearthed one detail after another. It ultimately led his American pursuers to the hole under a farmhouse near Tikrit — Saddam’s hometown — where the former dictator was discovered hiding on Dec. 13, 2003.

Approximately 600 troops participated in the hunt, which was called Operation Red Dawn.

Mr. Maddox, who originally was stationed in Los Angeles as an Army interrogator of illegal Chinese immigrants, was deployed to Tikrit in 2003 to help Delta Force soldiers track down “low-level bad guys who were killing our soldiers,” he said.

Mr. Maddox said he began hearing information that made him suspect that Saddam’s bodyguard, Mohammad Ibrahim, might be in Tikrit.

There, Mr. Ibrahim’s son was arrested as well, and told Mr. Maddox his father and his father’s friends liked to spend time at a fish pond south of Samarra, a town between Tikrit and Baghdad. There, soldiers found and arrested a cousin of Mr. Ibrahim, who said during his interrogation that their mutual aunt and uncle lived in Baghdad, and that Mr. Ibrahim was probably there.

Delta Force soldiers did, in fact, find and arrest Mr. Ibrahim in Baghdad shortly after he moved there. At 1 a.m. on Dec. 13, 2003 — Mr Maddox’s last day of tour in Iraq, with a flight leaving Baghdad later that morning — he began interrogating Mr. Ibrahim about where to find Saddam.

Ultimately, the promise to free Mr. Ibrahim’s relatives and to spare his wife and child the chaos of a visit from Delta Force operatives persuaded the bodyguard not only to reveal Saddam’s hiding place, but to personally lead American soldiers to a house that already had been searched. At that farmhouse, Saddam had prepared a manhole-sized, 6- to 8-foot-deep hole with a ventilation shaft and near-perfect concealment with bricks and dirt.

Inside it, at 8 p.m. on the same day Mr. Maddox began questioning Mr. Ibrahim, American soldiers found a resigned and disheveled Saddam. The dictator ultimately was convicted by a special tribunal of crimes against humanity and hanged in December 2006.

With 15,000 American soldiers in control of Tikrit, a city of 20,000, it was intelligence rather than power alone that captured Saddam.

“We owned this place and he was there the whole time,” Mr. Maddox said.

First Published: April 22, 2015, 8:18 p.m.
Updated: April 23, 2015, 3:25 a.m.