
On September 20, 2018, four people were shot and killed outside a Rite Aid distribution center in Aberdeen, Maryland, United States. The shooting occurred 30 miles (48 km) northeast of Baltimore. This was the second mass shooting in Maryland in 2018, following the Capital Gazette shooting.

Yosef (Joe) Alon, born Josef Plaček known also as Joe Alon, was an Israeli Air Force officer and military attache to the U.S. who was mysteriously shot and killed in the driveway of his home in Chevy Chase, Maryland.

The D.C. sniper attacks were a series of coordinated shootings that occurred during three weeks in October 2002 in the District of Columbia, Maryland, and Virginia. Ten people were killed and three others were critically wounded in the Baltimore-Washington Metropolitan Area and along Interstate 95 in Virginia.

On June 28, 2018, a mass shooting occurred at the offices of The Capital, a newspaper serving Annapolis, Maryland. The gunman, Jarrod Ramos, killed five employees with a shotgun and injured two others who were trying to escape. Ramos was arrested shortly thereafter. He pleaded guilty but not criminally responsible to 23 charges; in July 2021, a jury found him criminally responsible.

Jonathan Cilley was a member of the U.S. House of Representatives from Maine. He served part of one term in the 25th Congress, and died as the result of a wound sustained in a duel with another Congressman, William J. Graves of Kentucky.

Stephen Decatur Jr. was a United States naval officer and commodore. He was born on the eastern shore of Maryland in Worcester County. His father, Stephen Decatur Sr., was a commodore in the United States Navy who served during the American Revolution; he brought the younger Stephen into the world of ships and sailing early on. Shortly after attending college, Decatur followed in his father's footsteps and joined the U.S. Navy at the age of nineteen as a midshipman.

Steven Francis Gaughan was an American policeman from Prince George's County, Maryland, assigned to the Beltsville District, Special Assignment Team of the Prince George's County Police Department. In June 2005, he was shot and killed by Robert M. Billett following a traffic stop in Laurel, Maryland.

Of the thousands of people murdered every year in the United States, several remain unidentified. Many of these individuals remain unidentified for years or even decades after their deaths. These cases include that of Tammy Jo Alexander, who was murdered in 1979 and remained an unidentified decedent until 2015, Reet Jurvetson, who was murdered in 1969 and whose body remained unidentified for 46 years, and Alisha Heinrich, a toddler thrown alive from the Interstate 10 bridge in 1982 and identified via genetic genealogy in 2020.

Kenneth N. Harris, Sr., a member of the Democratic Party, was a candidate for Baltimore City Council President. He served on the city council since 1999, representing Baltimore's 4th Council District, until 2007. On September 20, 2008, Harris was shot and killed outside of a jazz club in northeast Baltimore.

Armistead Thomson Mason, the son of Stevens Thomson Mason, was a U.S. Senator from Virginia from 1816 to 1817. Mason was also the second-youngest person to ever serve in the US Senate, at the age of 28 and 5 months, even though the age requirement for the US Senate in the constitution is 30 years old.

On September 20, 2018, four people were shot and killed outside a Rite Aid distribution center in Aberdeen, Maryland, United States. The shooting occurred 30 miles (48 km) northeast of Baltimore. This was the second mass shooting in Maryland in 2018, following the Capital Gazette shooting.
Bronza M. "Bronzie" Parks was an American boatbuilder from Wingate, Maryland. Parks was the last builder of Chesapeake Bay skipjack sailing vessels.

Dustin John Higgs was an American man who was executed by the United States federal government, having been convicted and sentenced to death in 2000 for his role in the January 1996 murders of three women in Maryland. Tamika Black, Tanji Jackson, and Mishann Chinn were all shot and killed near the Patuxent Wildlife Research Center, on the Patuxent Research Refuge in Prince George's County, Maryland. Because this is classed as federal land, he was tried by the federal government rather than by the state of Maryland. His case, conviction, and execution were the subject of multiple controversies.

Major-General Robert Ross was an Irish-born officer in the British Army who served in the Napoleonic Wars and its theatre in North America in the War of 1812.

Brian Stephen Howser known by his ring name Shane Shamrock, was an American professional wrestler best known for his time Maryland Championship Wrestling. He is the only wrestler to win the Light Heavyweight Champion in the company's history, having become the inaugural champion two months before his death.