Veronica Guerin was an Irish journalist whose beat was crime. This did not sit well with the criminals whose exploits she covered, even though she used psuedonyms (mostly in order to avoid trouble with Irish libel laws). She received threats to her life and wellbeing, but did not allow this to deter her.
A particular foe of hers was mob boss John Gilligan, who threatened to kill her and rape her son after she confronted him about his wealth and apparent lack of legitimate income. On June 26, 1996, men from his organisation (although, according to Gilligan, acting without his knowledge or consent) shot and killed Guerin in her car.
The murder weapon was never recovered, but an investigation led to several convictions for her murder and for other charges related to their involvement in organised crime. Gilligan was not convicted of the murder, but was put away for drug-related charges.
The most lasting legacy of Guerin’s murder was the formation of the Criminal Assets Bureau, which conducted precisely the sorts of investigation that Guerin had advocated and that led to her death.