Clarence Barbour became Chief for the first time in 1917, having previously owned a café on West Hargett Street.  He had served as a patrolman years before, leaving to run the café.  He took the oath of office on June 30th, assuming duties the next day.  Almost immediately, Chief Barbour began making small changes in police regulations – they were no longer allowed to smoke on duty, and must be in uniform when signing in and out of their shifts, for example. 
Chief Barbour had only been in office for a couple of months when the single plainclothesman (detective) on the force resigned without recommending a replacement. The following month, two officers were dismissed for insubordinate comments made when the department’s petition for a cost-of-living increase in salaries was turned down.  These officers were replaced by Thomas Crabtree and J. G. Strother.
In June of 1918, Chief Barbour married Martha Staples in Virginia, and the couple settled into a house on Fayetteville Street. Like his predecessors, Clarence Barbour devoted a lot of time and energy to the pursuit of bootleggers, due to Prohibition.  With the onset of the draft for World War I, he also found himself being required to pursue draft dodgers, including working with state and federal agencies to conduct a raid on a locally-held carnival in the summer of 1918.  Earlier in the year, he had been busy conducting a registration of German citizens living in Raleigh – first men in February, and then women in June, as required by an act of Congress.
Clarence Barbour left the Raleigh Police Department in March of 1920 to pursue an opportunity in the wholesale grocery business.  His letter of resignation stated that he had “an opportunity to engage in a business that seems more profitable.”  He would return to the police department about a decade later, however, once again serving as Chief.  In addition to running a café, he had worked as a sheriff’s deputy during that period. 
Chief Barbour, working with the newly-elected Commissioner of Public Safety, Carl Williamson, was already planning to bring about changes in both personnel and procedure within the department when he took the oath of office on May 12, 1931.  (Incidentally, Harold L. Pierce, who would later serve as Chief, took Barbour’s place as sheriff’s deputy.)  In less than two weeks, a desk sergeant and two patrolmen were dismissed from the force, the head of detectives was demoted and replaced, and a clerk/stenographer had also been replaced.  By June, the police were cracking down on bootlegging, as well as raiding purported gambling dens.
In June of the following year, Chief Barbour was required to reduce the police force by four officers, due to budget cuts.  This resulted in shifting around of personnel as well, with the current head of detectives returning to plainclothes duties, and Chief Barbour assuming his former duties.  In October of 1932, Chief Barbour attempted to improve traffic conditions in downtown Raleigh by forming an eight-man team under Lieutenant Luther Chalmers, outfitted with distinctive uniforms.
In March of 1935, Chief Barbour resigned for a second time, citing his reason as the desire to support the proposed change to a city council/city management form of government.  He felt that, with the upcoming election on this change, he couldn’t hold office under the current city commissioners, who did not support it.  He would later express disapproval of the city commissioners form of government, which he saw as rife with undue political patronage.  Clarence Barbour died in Jacksonville, Florida, in 1975, at the age of 90.