During the early twentieth century, technology was extremely elementary and the use of fingerprint technology was even rarer. There were only two certified, professional fingerprint experts in the state of Kansas. Unfortunately for the Fleagle Gang, Roland S Terwilliger "Twig" was one of them.
Twig played a major role in the apprehension of the Fleagle gang. Due to the care and precision he used in lifting the impression of Jake Fleagle's right index finger, the identities of the Lamar bank robbers were solved. His role in the capture of the Fleagle brothers brought him great acclaim and a share of the reward.
Terwilliger's early history did not foretell a career in law enforcement. In 1915, during World War I, Twig served as an auto mechanic and machinist. This experience led to a career as a garage owner and operator. Twig started his career in law enforcement as a vigilante. These were men in Kansas that were law abiding citizens who were allowed to purchase firearms and ammunition at government costs. Out of the 105 counties in Kansas, 90 of them had these vigilantes. Terwilliger studied and completed a correspondence course in fingerprinting and the Bestillon system of police identification. Following this he became a police officer in Garden City, Kansas, then served as deputy chief and finally in 1931 through 1934, sheriff of Finney County.
He later moved to Colorado Springs where he operated his own gunsmith shop and eventually was employed as a mechanical engineer with the Alexander Film Company
In June of 1928 a copy of the partial fingerprint found on the rear window of Dr. Wineinger's car was sent to the FBI in hopes off finding a match. One year later, FBI fingerprint expert, Albert B. Ground, was examining a fingerprint card from an individual suspected of having participated in a train robbery in Stockton, California. He noticed something familiar in the pattern of the right index finger and was able to match the print to that of Jake Fleagle who had been living in California under the alias William Harrison Holden.