The American Society of Journalists and Authors has awarded its prestigious Conscience in Media Award to slain journalist Daphne Caruana Galizia.

The Conscience in Media award recognises journalists who knowingly have endured great personal costs while pursuing the highest tenets of their profession, ASJA president Sherry Beck Paprocki said. This selective award has been presented only 12 times since 1975.

Ms Caruana Galizia, 53, was murdered in a car bomb last October. Since the murder, the journalist and blogger has been showered with overseas honours. 

“Daphne Caruana Galizia represents the highest ideals of journalism: Courage, sacrifice and a firm commitment to the truth,” said Sally Wendkos Olds, chair of ASJA's First Amendment Committee.

"Her bravery and dedication are especially inspiring to us as fellow independent writers.

Ms Caruana Galizia's son Matthew added: "Before the assassination that finally silenced her, her house was set on fire on two occasions while family members, including the children, were inside. “After the second arson, police concluded that the attackers were from the military (the Armed Forces of Malta), but they were never able to make an arrest."

Similarly, although three people were arrested in the car-bombing that killed her, whoever ordered the assassination has not been identified or charged. Despite her death, her legacy lives on, he said.

The Conscience in Media award will be presented on May 18 at the Sheraton Times Square in New York during ASJA’s annual conference. 

The award calls attention to the increasingly dangerous profession of investigative journalism. More than 700 journalists have been killed over the past decade, according to Reporters without Borders (RSF). 

Founded in 1948, ASJA is the US's professional organisation of independent nonfiction writers.