Gaithersburg Police Department

1963–1986: Founding

The Gaithersburg Police Department was founded on April 1, 1963,^[7] when a resolution creating it was signed into law by the mayor of the city at the time, Merton F. Duvall.

The town budget for fiscal year 1964 included "police protection" salaries for the solitary officer amounting to $4,000 (equivalent to $41524 today), and equipment purchases of $500 (equivalent to $5190 today).

It was under the administration of Chief DeVries that the Gaithersburg city police began to operate under its current system of dispatch through the Montgomery County Police Department. As a former Montgomery County Police lieutenant, DeVries was in a position to work with the County Police in a way that had previously not been possible.

1986–1998: Expansion and modernization

The Gaithersburg Police Department grew from an authorized strength of three sworn officers and one civilian clerk in the early 1970s, when the city's population was 7,000, to its current complement of 57 sworn officers and nine civilians. The majority of that growth occurred from 1986 to 1998 under the direction of then-chief Mary Ann Viverette.

In 1983, the GPD formed a traffic unit.

Viverette was the GPD's chief from 1986 until her retirement in May 2007. John King succeeded Viverette and served until 2010. The GPD currently falls under the leadership of Shawn Eastman, who became the chief after the retirement of Mark P. Sroka in March 2026.

Personnel

From 1971 to 1990, the Gaithersburg Police Department only hired officers who had former experience as police officers.

The majority of the Gaithersburg's police officers have come from other agencies. The experience of these officers comes from agencies such as Montgomery County, Washington, D.C., United States Secret Service, Montgomery County Sheriff's Office, Maryland National Capital Police, and Baltimore City, to name a few.

Chiefs

David Marstiller was the first Chief of Police,^[8] although there are references to a "Town Marshall" in the minutes of Town Council Meetings prior to 1963.

Over the years, there would be several chiefs of police; James Tassie, formerly of the Rockville City Police Department; Marson Johnson, who had been an officer in Michigan; John F. DeVries and George Fusco, both of whom had retired from the Montgomery County Police Department as lieutenants.

List of chiefs

No.	Chief		Rank	Life	Tenure	Notes
1		David Marstiller	Chief
2		James Tassie	Chief			Former Rockville City Police Department officer.
3		Marson Harry Johnson, Sr.	Director of Police Services[9]	February 20, 1941 – June 11, 2004 (aged 63)	1974–1977	Former Michigan policeman.
4		John F. DeVries, Sr.	Chief	Died in 1981 at age 52.[10]	1977–1980	Former MCPD lieutenant
5		George Fusco[11]	Chief		1981–1986	Former MCPD lieutenant.
6		Mary Ann Viverette[12]	Chief		1986–2007[13]	Retired in May 2007
7		John King[14]	Chief		2007–2010
8		Mark P. Sroka[15]	Chief[15]		2010–2026[15]
9		Shawn Eastman[3]	Chief[3]		2026–present[3]