Who is Thomas Byrnes and why did he have to change law enforcement?

Thomas Byrnes became one of the most famous crime fighters of the late 19th century

Explanation:

Thomas F. Byrnes was an Irish-born American police officer, who served as head of the New York City Police Department detective department from 1880 until 1895, who popularized the terms "rogues gallery" and "third degree".

Explanation:

The nineteenth-century saw the rise of the professional detective, both public and private, as a leading figure in the fight against crime. On a city police force, it was no longer sufficient for an officer to grab a ne’er-do-well off the street and throw him into jail, he must also gather the evidence and testimony needed to convict the perpetrator. The force needed men—and sometimes women—with the ability to read clues and follow the trails of a criminal class growing ever more sophisticated at eluding detection. In the private sector as well, agencies sprang up to provide these services to those who, for whatever their reason, were not interested in making their investigations public.  New York City Police Inspector Thomas F. Byrnes, almost singlehandedly transformed the department from a collection of club-wielding thugs to a modern, efficient crime-fighting organization. Under Byrnes’s leadership, police procedures were standardized and criminal information was stored systematically; the New York City Police became the model for police departments throughout the country.

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