With the retirement in the latter part of 1939 of Police Chief J.E. Robinson, John B. Balthrop was to take over his commanding officer. He would begin 1940 with two motorcycles, one car and ten full time employees. Lt. George McCraw, Irvin W. Blackwell, Issac H. Buck, Adolphus D. Curtis, Robert I. Hall, Louis B. Kirby, John Lee, William T. Milling, James A. Rinehart and Workhouse Keeper, Carney Baggett would make up his police force.

In 1940, Clarksville's population was only 11,822, surpassing its neighboring city Hopkinsville, Kentucky population by 41 people. William Kleeman was serving his first term as Mayor; Charles Runyon was City Attorney; Matt Lyle was Attorney General; Ridley Goodpasture was General Sessions Court Judge; John T. Cunningham was criminal Court Judge and W.B. Corlew served as Magistrate. W.E. Beaumont was Sheriff and S.B. Odom and Clyde Keeton represented the Highway Patrol. The Fire Department was manned by Chief John Roche with five fire fighters.

In March of 1940 the department received a new police car, a 1940 model Chevrolet, four door black sedan which replaced the 1938 Ford which had been used. In addition, the City authorized the purchase of $150 of fingerprint equipment.

Patrolman John Lee returned from F.B.I. School, one of only three selected from the state of Tennessee to attend this school. Later in 1940 Patrolman Lee was to teach the first study period in the Clarksville Police training school designed by the F.B.I.

In June of 1940 the Police Department reported 63 arrests made with fines assessed in the amount of $732.00 and a collection of $551.50 in fines. By the end of the year the total would be 734 arrests; 644 men and 70 women. Many of these defendants participated in a city street gang which paid $1.00 a day. $1,588 was paid for their work during the year.

A recommended budget of $20,000 for the Police Department was approved by the City Council for 1941.

Montgomery County's first criminal case which depended materially upon scientific ballistics was presented by Patrolmen John Lee.

The position of Sergeant was approved by the City Council and John Lee was chosen to fill the slot. The salary for patrol officers was $100 a month with the Sergeant making $120 a month.

Chief Balthrop attended a 2-day school in Memphis, Tennessee designed to train officers in the event of an invasion of the Unites States. Subject matter included black-out enforcement, air raid precaution work, looting problems and general war duty. Clarksville was seriously preparing for the possibility of foreign invasion.

By the end of 1941, there were 704 arrests, 653 men and 51 women with fines assessed in the amount of $7,453.

1942 opened to find Clarksville experiencing a "boom-town" trend. Camp Campbell had become a reality and was being patrolled by four additional officers: H.T. Cook, Glen Morrow, Irving Rinehart, and Charlie Vaden. James Moore was also to be hired later in the year. The city also began considering a radio system and invited the county to participate.

Lt. George McGraw left the Clarksville Police Department to take a job with Camp Campbell and Jim Rinehart was named acting lieutenant.

With the influx of soldiers from all over the United States, the police department really had its hands full. One week alone found the arrests of 23 people. Clarksville now had to deal with drunken brawls, increasing numbers of disorderly conduct calls, prostitution problems and rising burglary/robbery cases.

The year would see the loss of police personnel as Sgt. John Lee left to take a government job which would eventually take him overseas; Issac Buck resigned to go to Camp Campbell; Charlie Vaden left to work for the B.F. Goodrich plant and James Moore would enlist in the army.

Lloyd Evans and W.T. Blackwell were appointed to fill out the roster and it became necessary to begin two shifts of six men each to patrol the city of 15,000.

Parking meters became a reality in September of 1942. By October the first parking meter robbery was reported as the equipment was destroyed for the alleged amount of fifty cents.

Clarksville was experiencing more than it bargained for, in its struggle to maintain its rising star status. The City found itself dealing with rumors of possibly being put off limits to Camp Campbell because of problems with prostitution and venereal disease. Chief Balthrop publicly vowed to resolve the problem. The Police Department, with the assistance of the County Health Department, made so many arrests that the City Jail could not hold them all, and out of necessity, the County Jail took in the overflow.

With the beginning of the New Year in 1943, the nation was still at war with Europe and Japan. The presence of Camp Campbell and its troops still dominated the city scene. New police officers included S.L. Wilson, Bayliss Seay, K.L. Nipple, R.I. Hall, Henry Cook and Howard Story.

The Police Department budget for 1944 was adopted by the City for the amount of $36,000. 1944 would also be the year the police motorcycle would be traded in for a new one.

May 1944 was reported by Chief Balthrop as being one of the busiest months for the police since the construction of Camp Campbell as fines collected totaled $2,123.

Patrolmen H.T. Cook and Louis Kirby were responsible for capturing two German war prisoners who had escaped from Camp Campbell and were attempting to leave town by hiding on a railroad car near 5th Street.

By the end of the year, the budget was ratified to allow for the trade-in of the old patrol car for a new one at the expense of $650. Also, the allowance for prisoner meals given to Workhouse Keeper Carney Baggett was increased from 25 cents to 35 cents.

Tragedy marred the local police scene as Patrolman K.L. Nipple was killed in an early morning fire on August 9, 1945. The Clarksville Laundry on Third Street caught fire; the two story structure burned quickly and threatened to take other nearby businesses with it. Patrolman Nipple, along with Firemen Marshall Hodge and Joe Davenport Jr., were standing in the doorway when a wall collapsed, hitting the individuals. Nipple was killed instantly.

The City Council met for the purpose of acting on recommendations to change the hours of patrol to eight per day instead of twelve. This would include the hiring of three new officers. The department currently operated on two 12 hour shifts with one day off per week. Under the new plan, a patrolman would work only 8 hours per day but would receive no days off except for vacation.

The Police Department budget for 1947 was adopted at $37,000.00. This increase was to include $1,500.00 for the employment of additional patrolmen. The new officers added were Leslie Suiter, Harlan Hogan and Maurice (Morris) Clark.

In September of 1946 the F.B.I. chose to hold its police training school at City Hall. Expected to attend were officers from Paris, Erin, Dover, Springfield, Dickson, Waverly and Ashland City. Courses would be conducted on fingerprinting, treatment of prisoners, laws relating to arrest, searches and seizures, mechanic of arrests and investigative aid of the F.B.I. The entire local force was able to take the course.

1947 opened with disturbances resulting from picket fights during a strike at the Acme plant. Later in the year, the City Council would authorize Mayor Kleeman to take action necessary to keep down the growing violence between strikers and non-strikers. Police Officers were selected to perform these duties as long as the strike continues.

The Police Department budget for 1947 was $40,000.00. Two new officers were added. The City Council also approved the employment of a third police officer whose duty was to inspect property in Clarksville to see that premises were being kept clean. This officer's duties would also include serving as a regular patrolman on Saturdays and Sundays.

In the August sessions of the City Council, it was voted unanimously for Bell Telephone Company to install a 2-way police radio system for Clarksville. The unit was to be furnished and maintained for $97 a month and units for the patrol cars would cost $22 per car. This would necessitate the installment of an antenna on the city water storage take on Cumberland Drive. Reaching 170 feet from the ground into the air, the antenna was reputed to be good for a 15-mile radius.

The FCC assigned the police radio call letters "WGTQ" which would be operating on a frequency of 155.01. On November 14, 1947, Mayor Kleeman sent the first message over the new police radio system: "Mayor Kleeman calling Chief Balthrop, over." Chief Balthrop responded with "Station WGTQ, time 10 o'clock a.m., go ahead Mayor."

"Chief this is a historic moment in the interest of Clarksville. The radio I am certain, will do much toward reducing crime and increase the efficiency of the police department. This radio adds much to the development and growth of Clarksville."

With that brief conversation, the Mayor, located in a police car on the street, and Chief Balthrop, at the transmitter in the police station in City Hall, the station officially went on the air.

Three days later, the police radio was credited with the arrests of at least three lawbreakers over the weekend.

In addition, retroactive to November 1, the pay raise ordinance passed by the City Council provided a flat 12 1/2 per cent raise to city firemen and police officers who had served over three months.

In 1948, we find another strike with the B.F. Goodrich plant being involved. Police were again used to insure that those desiring to return to work could do so.

Two city officers responding to a shots fired call in a local cafe in East End found themselves surrounded by an unruly crowd of nearly 100 when they attempted to arrest a Camp Campbell soldier. They managed to hold off the crowd with a sawed off shotgun and pistol until other officers and several jeeps of military police arrived.

In June of 1948, new traffic lights were installed and officially turned on in the downtown Clarksville. The main intersection lights were to be controlled by the Police Department. A key would be used to open a switch box that would allow officers to hold traffic for as long as necessary.

In August of 1948, the City Council session approved hiring four more policemen. This would enable the force to then work only 6 days a week for 8-hour shifts with one day off. It was agreed to purchase new uniforms for the 16-man force.

In early 1949, the Clarksville City Jail was renovated at no labor cost to the City. Inmates painted walls, floors, ceilings, bunks and cell bars to shorten their jail sentences.

For the fiscal year ending June 30, 1949, the Police Department reported 2,400 arrests; 2,219 men and 181 women. Fines totaled $29,092.50 and the entire police force was re-elected in the City election.

The Clarksville Police Department shown brightly in November of 1949 as Officers Ralph Turney and Louis Taylor captured a fugitive from justice who had eluded officers in three states. The fugitive, recently released form federal prison in Atlanta, Georgia, had stolen a car in North Carolina and was on his way to Oklahoma when he made the mistake of going through Clarksville. The fugitive attempted to run down the two officers as they got out of their patrol car. Despite this attempt, the two officers were successful in their attempt to place the suspect under arrest.