In July of 1921, The Indiana General Assembly created the Motor Vehicle Police as a means to combat the increasing problem of car theft in the state.

In 1925, the force was finally granted police powers, however an officer could not arrest even a known criminal unless he was also a traffic violator! In 1933, the Indiana State Police was formed under the umbrella of the new Division of Public Safety with 66 new recruits.

By 1937, that number increased to 170 officers. In 1939, the ISP had the distinction of being the first law enforcement agency in North America to have authorized the use of a chemical test to determine levels of intoxication with the famed "Drunkometer".

This was followed in 1955 with an improved version of the device called the Breathalyser invented by ISP Captain R.F. Borkenstein. This successful device has been used by police agencies around the world to assess impairment by alcohol in driving offenses. In 1947, an aviation division was created and in 1951, 25 new full time officers were hired for the new Motor Carrier Division to address commercial vehicle traffic regulations.

The Bureau of Criminal Investigation was formed in 1998. Today, the ISP continues its mandate of working with communities to improve public safety, enforcing traffic and drug laws, investigating crimes and enforcing the laws and regulations pertaining to commercial motor vehicles.

“STATE OWNED” titled license plates for ISP vehicles were introduced in 1942. The plate measured approximately 5 1/2”x12” and had dark blue characters embossed over a yellow base. The title STATE OWNED CAR occupied the top portion of the plate. Below the title was a number up to three digits. Below that was INDIANA-42 along the bottom of the plate. It is possible that these plates were multi-year plates in an effort to preserve metal during the War effort, as no examples or records of this type exist for 1943 until 1946.
STATE OWNED license plates used by the ISP from 1947 until the 1960's took-on the same layout and colors of regular passenger license plates being used at the time.
It was not until 1979 that the Indiana State Police began issuing graphic agency-titled license plates of their own which continue until this day.

License Plates of the Indiana State Police

The earliest license plates used by the patrol cars and motorcycles of the ISP were standards issue passenger and motorcycle plates. Although there was no special number bloc reserved for ISP license plates, it does seem like an odd coincidence that most license numbers used on ISP cars seen in photos from the 1930's began with either 125-### or 126-### .

It is believed, but not confirmed that some ISP vehicles in the early 1940's used the five-point star prefix license plates that were reserved for official state vehicles. There is no evidence yet to either confirm or refute that hypothesis.

1947 issue: Embossed steel. Approximately 5 1/2”x 12” Blue over yellow. INDIANA at center top of the plate over SO prefix and up to three numbers over 47 at center bottom of the plate.
1948 issue. Embossed steel. Approximately 5 1/2”x 12” White over blue. 48 at center top of the plate over SO prefix and up to three numbers over INDIANA at center bottom of the plate.
1949 issue. Embossed steel. Approximately 5 1/2”x 12” White over red. INDIANA at center top of the plate over SO prefix and up to three numbers over 49 at center bottom of the plate.

1950 issue. Embossed steel. Approximately 5 1/2”x 12” Yellow over black. 50 at center top of the plate over SO prefix and up to three numbers over INDIANA at center bottom of the plate.
1951 issue. Embossed steel. Approximately 5 1/2”x 12” Black over white. 51 at center top of the plate over SO prefix and up to three numbers over INDIANA at center bottom of the plate. This plate may have been used for 1952 and 1953 as well, as passenger and commercial license plates in Indiana were validated by use of tabs for those latter years. It is believed that State Owned vehicles did not. There is a photographic example of a 1952 State Owned plate # 124 pictured below, however there is no record of these plates being issued.

1954 issue. Embossed steel. Approximately 5 1/2”x 12” White over maroon. 54 at center top of the plate followed by legend STATE over OWNED to the left of three embossed numbers over INDIANA at the center bottom of the plate. 1955 plates in Indiana were validated by a tab on the 1954 base plate. Therefore this issue would have been used for both 1954 and 1955.

The years 1956 through 1964 pose more questions than answers for ISP license plate usage. It is believed that SO prefixed license plates continued to be used through to 1963, however there have been photographs unearthed which show a fully-embossed STATE over OWNED embossed prefix for 1957 and 1958, and for the undated issue that came after it around late 1959/early 1960. Yet there is also a photo from 1961 showing an ISP patrol car using a dated 1961 license plate with the older SO prefix again. It is unknown if these were exceptions or the rule until we can achieve more confirmed information or period photographs.
Until then, I will document the chronological versions based on what we know and what we can assume based on established pattern. All license plates from 1956 onward are standard 6”x12”.

1957 issue. Embossed steel. Dark blue over deep yellow. IND-57 at center top of the plate over SO prefix and up to three numbers over slogan DRIVE SAFELY embossed in yellow within a dark blue rectangular field at center bottom of the plate.

1958 issue. Embossed steel. Deep yellow over dark blue. Slogan DRIVE SAFELY embossed in blue within a yellow rectangular field at center top of the plate over STATE over OWNED prefix and up to three numbers over IND-58 at center bottom of the plate.

1959/1960 issue. Embossed steel. White over deep red. INDIANA at center top of the plate over STATE over OWNED prefix and up to four numbers over slogan DRIVE SAFELY embossed in deep red within a white rectangular field at center bottom of the plate.

As per the photo shown above, it appears that at least for 1961, the ISP returned to SO prefixed license plates. Therefore I will make my estimations for 1962 and 1963 based on the 1961 plate.
1962 issue. Embossed steel. Deep yellow over black. Slogan SAFETY PAYS embossed in black within a yellow rectangular field at center top of the plate over SO prefix and up to four numbers over IND-62 at center bottom of the plate.
1963 issue. Embossed steel. Deep yellow over blue. 1963 at top center of plate over SO prefix followed by up to four numbers over INDIANA at center bottom of plate.

In March of 1979, the Indiana State Police announced that as of July 1 1979, all marked ISP cars would be sporting new graphic license plates "...because there was a need to change state plates to distinguish State Police vehicles from others".   
The attracive graphic-designed plates were manufactured by the Division of Industries & Farms of the Indiana Department of Corrections for $2.01 each using Indiana BMV blanks.
The plate consisted of the state name silkscreened in dark blue in the top center of the plate using upper case letters. Directly below was a four digit number between 2000 and 4999 embossed in medium blue. In the bottom center of the plate also silkscreened in dark blue is the title State Police in upper and lower case letters. To the far left of the plate is an attractive graphic of the state silhouette in dark blue trimmed in bright yellow. The center of the graphic features the state flag center of the torch and stars. Just prior to 1981, these plates were run front and rear on ISP patrol vehicles. Once a directive came down from Headquarters to run the plates rear only, upwards of 75 front license plates had gone missing. As a result, these ISP graphic license plates are now under strict controlled inventory protocols, and if a trooper's plate goes missing, there are unpleasant times ahead for him or her.
It has been stated by a retired ISP insider, that all the turned-in ISP license plates to fleet (at least during HIS time) were buried in a deep pit somewhere on HQ property.
Twenty five samples of this license plate bearing the number 45678 were made and distributed to ISP and other state dignitaries including the Governor when the license plates were unveiled.
The simple yet attractive design was so popular, that it continues to be issued to this day.

Indiana State Police Front License Plates

The Indiana State Police had been issuing license in pairs from 1933 until at least the late 1950's. Once the front license plate was no longer needed, most ISP patrol vehicles ran nothing on the front end of the car.
In 1966, the state of Indiana celebrated 150 years of statehood. The state had made and issued special commemorative “booster” license plates that were run on the front of ISP patrol cars for that year.
Otherwise and since that time, a variety of other booster plates have been run on the front of ISP vehicles at the discretion of Command Staff.
Here are a few such examples.

Indiana State Excise Police

The Indiana State Excise Police is the law enforcement division of the Alcohol and Tobacco Commission. State Excise police officers are empowered by statute to enforce the laws and rules of the Alcohol and Tobacco Commission as well as the laws of the State of Indiana. Their mission is to provide quality service and to protect the morals and welfare of the people of the State of Indiana. The history of license plate issuance for this agency is non-existent. There are only a couple of known examples thusfar and are featured below. Based on materilas and layout, they are believed to be from the 1950's into the 1960's. Any other information about this agency's license plate issuance history would be appreciated.

Indiana State Police Motorcycle License Plates

Indiana State Police have had motorcycles in their fleet since the earliest days. For the most part, they ran regular Indiana motorcycle plates on the rear and curved front fender sign which read INDIANA over STATE POLICE on both sides.
It has been stated that in 1937, a dated blue over yellow license plate that read IND over STATE over POLICE was issued, however no confirmation or photo has been seen of this type.
An SO-prefixed motorcycle plate for 1965 has been confirmed, however it is unknown if there had been any previous issues of this type or any subsequent.
In later years, a photo taken from a distance shows an ISP motorcycle on a staged traffic stop photo where it appears to bear a miniature version of the graphic ISP car plate. The numerals 4426 appear stylized and screened as opposed to embossed.
More recently, ISP motorcycles appear to bear all-screened standard Indiana motorcycle plates in the M2##A series.

Indiana State Police Alliance License Plate

The Indiana State Police Alliance (ISPA) was established in 1974 as an association of Indiana State Troopers with a focus toward promoting better law enforcement to the citizens of Indiana and gaining state-wide support for Indiana Troopers. They have issued a series of promotional or "booster" plates for their members and supporters.

Indiana State Police Memorial License Plate

ISP Memorial License plates are available to anyone who wishes to support the Indiana State Police. Proceeds from the sale of these plates go to the Indiana State Police Memorial Fund, which supports the Youth Education and Historical Center and maintains the ISP Memorial and Eternal Flame.