This week marks the 125th anniversary of the start of a notorious chapter in New Orleans history. On Oct. 15, 1890, Chief of Police David Hennessy was gunned down as he walked to his house on Girod Street. As Hennessy lay dying in the street, a fellow officer reportedly asked who shot him. The chief allegedly responded, "Dagos," an ethnic slur for Italians. Hennessy died 10 hours later and his alleged words to that officer ignited a period of lawlessness unlike any the city had seen. Police rounded up dozens of Italians, and prosecutors later indicted 19 men. Hennessy reportedly had stepped into a dispute between rival groups of Italian immigrants, and some people believe that led to his murder. Subsequent trials in 1891 ended with hung juries and acquittals and gave rise to the phrase with which the defendants were taunted, in fake Italian accents: "Who killa da chief?" On March 14, 1891, after a rally at the Henry Clay statue on Canal Street, a mob of New Orleanians stormed the parish prison, fatally shooting and hanging 11 Italian men. The headline in The New York Times read "Chief Hennessy Avenged...Italian Murderers Shot Down." The vigilante violence, prompted by fears of the Mafia and supported by Mayor Joseph Shakspeare, touched off a diplomatic crisis between the U.S. and Italy. No one ever was jailed for the lynchings of the Italians, and the effect on Italian-American relations in the city was felt for decades.