The City of Arnold was incorporated on September 18, 1972. The first Police Personnel Board was appointed November 2, 1972.

Their initial task was to hire the city’s first police officers so they could begin patrolling the streets of Arnold. Those serving on the first Board were Ray Adams, Chris Hansen, and Gene Whiteaker.

On November 15, 1972, Joseph Beil was appointed as the first Chief of Police, and Adrian Barrett was appointed as the first Assistant Chief of Police by Mr. Ferd Lang who was appointed as the city’s first Mayor. Other appointed officials were Robert Brown, as City Attorney, and Robert Eisenhauer as City Judge.

During the inception of the Arnold Police Department, which was housed along with City Hall in a small rental space at 522 Jeffco Blvd., police transportation was limited to say the least. Money was borrowed from incorporation funds to purchase the department’s first police car.

On December 21, 1972, the first car was delivered and with a set of red lights that were donated by the St. Louis County Police Department, the vehicle was put into operation.

The first officers who began patroling the new city streets were; Chief Beil, Assistant Chief Barrett and six full time officers: Ray L Hedrick, Murvel E. Collier, James T. Curtis, Frank L. Nelson, David L. Colnaghi, and Les Burns

Assistant Chief Barrett, who was in poor health passed away while in office and on April 1, 1973, Officer Curtis was promoted to the position of Captain/Assistant Chief of Police.

The first Arnold Police Department telephone line was installed on January 18, 1973. Anyone calling the new number (296-2222) was connected with the Jefferson County Sheriffs Department.

During the first seven months of operation, two way radio communications between officers on the street and the Jefferson County Sheriffs Department were non existent. This was because the police cars were not yet equipped with mobile radios.

In order to alert an officer that a call was pending, the Jefferson County Sheriffs Department had to call someone at the old Brouk-Ziegler Company which was located in a building at 945 Jeffco Blvd. and they would signal the police officer by hoisting a red shop towel up a pole. When the officer drove by and saw the red shop towel signal, the officer would stop and pick up the message and go on the call.

To keep the fledgling police department running, on January 11, 1973 Joyce O'Mally was appointed as the Police Department’s first Secretary/Matron.She performed her duties on a voluntary basis until she was placed on the payroll on September 24, 1973.

In July of 1973, two-way radios were installed in the police cars and the Communications Division was established. The first dispatchers hired were: Dave McDonald, who served as the department’s Head Dispatcher, Curt Tary, Ron Reed, Bob Ziets, and Frank Pisciotta. At that time, the Communications Division also dispatched for the Rock Community, Springdale and Shady Valley Fire Protection Districts.

As the city began to grow in size, additional officers were hired and the current rank structure of the department began to form. In July of 1973, James T. Curtis was appointed as Acting Chief of Police when Chief Beil resigned. On September 6, 1973 acting Chief of Police James T. Curtis was promoted to Chief of Police, Robert York Jr. was promoted to Major/Assistant Chief of Police, and Frank Nelson, Murvel Collier, and Ray Hedrick were promoted as the department’s first Sergeants.

In May, 1978, Officer Melissa Crane was hired as the first woman commissioned Police Officer for the City of Arnold.

September of 1989 brought on the retirement of Chief Curtis and Captain B.J. Nelson was appointed Acting Chief of Police until his appointment as Chief of Police on March 8, 1990. In April 1998 Chief Nelson retired, and in December 1998, Dale Fredeking was appointed as the department's fourth Chief of Police. In September 2001, Lieutenant Robert Shockey, a 17 year veteran of the department was appointed Chief of Police.

Today the Arnold Police Department is comprised of 48 sworn officers, 8 dispatchers, and 4 clerks/secretaries.