The Police Detective: Evolution & Duties

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  • 0:30 Police Detectives
  • 0:57 Rise of the Police Detective
  • 1:59 J. Edgar Hoover
  • 3:26 Modern Laws
  • 4:33 Duties & Types of Detectives
  • 6:11 Lesson Summary
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Lesson Transcript
Instructor: Jessica Whittemore

Jessica has taught junior high history and college seminar courses. She has a master's degree in education.

Learn about the history of the U.S. police detective. Then learn about the duties of being a detective and the different types of police detectives. Test yourself at the end with a short quiz.

Police Detectives

If you turn on any channel at almost any given time, you will most likely come across a TV show glamorizing the job of the police detective. Years ago, we chose from Columbo, Kojak, and Hill Street Blues; now, shows like the CSI: Crime Scene Investigation series are all the rage. However, what is seen on TV doesn't really tell the full story. Let's take a look back at some of the earliest detectives so we can see how the position has evolved to what it is today.

A police detective is a member of the police force who investigates crimes. They do this by a number of means, including gathering and analyzing evidence and interviewing witnesses. A detective is kind of like the Sherlock Holmes of a police department. However, these individuals usually don't wear floppy coats and funny looking hats. Instead, they try to blend in, wearing plain clothes and driving unmarked cars.

The Rise of the Police Detective

Although it's familiar to most of us, the position of police detective is actually a rather modern one. In fact, it wasn't until the late 1850s that the New York City Police Department gave America its first detective bureau. Now, this doesn't mean that police weren't patrolling the streets before this. It simply means crimes weren't usually being systematically investigated nor was evidence being compiled in a preset manner.

In the late 1870s, Thomas J. Byrnes, a native of Ireland, became America's first renowned police detective. Due to his intensive questioning techniques, which included beating and other forms of interrogation that would be considered torture now, many sources consider him as having originated the term, 'third degree' - a pun combining his name and his interrogation techniques. In any case, Byrnes solved famous crimes like the famous Manhattan Savings Institution robbery. With this, he was named Chief of the New York City Detective Bureau.

J. Edgar Hoover

Of course, much has changed since the days of Byrnes. For instance, his rather aggressive questioning techniques would definitely not fly these days. Also, the unchecked power of men like Byrnes led to a great deal of corruption within the world of police detection. During the late 19th century, the detective agencies of cities like New York and Chicago were nearly paralyzed by officer corruption. In many ways, it was hard to tell the good guys from the bad guys.

In order to fight this unchecked power and penchant toward corruption, the federal government got involved. In the 1920s, J. Edgar Hoover became the first director of the Federal Bureau of Investigation. As the leader of the nation's premier detective agency, Hoover created a system of accountability for detective agencies across the land. No longer were city departments allowed to make their own rules.

Also, Hoover worked to create a separation between police detectives and the community. He realized this must happen in order for detectives to maintain professional perspective. Rather than detectives spending their whole careers covering the neighborhoods in which they lived, the FBI moved its detectives regularly from place to place. To put it mildly, Hoover led a powerful bureaucracy that sent rules and standards down from the top. For instance, he mandated educational requirements and formal training for all who carried the name 'detective' on their badges.

Modern Laws

The decades following the reign of Hoover saw the federal court systems make additional changes to how modern police detectives gather evidence today. For instance, the early 1960s saw the court passage of the exclusionary rule. This law prohibits the use of illegally obtained evidence in a criminal trial.

The 1960s court cases of Mapp vs. Ohio and Miranda vs. Arizona also changed the detective business. Mapp vs. Ohio states a suspect has the right to attorney representation during interrogation. Of course, this made it rather impossible for detectives to employ the violent third degree tactics of men like Byrnes. Similar to this, Miranda vs. Arizona requires all suspects must be read their rights when taken into custody. If not, anything a police detective gathers through interrogation or investigation runs the great risk of being inadmissible in court.

Though some argue that these laws have made the job of police detective more difficult, just as many believe it has made the title of police detective a respected one.

Duties and Types of Detectives

The role of the modern police detective is a multi-faceted one. Just like in the days of Hoover, detectives must have special training and education in investigative techniques and legal procedures. Still in force today, the Exclusionary Rule, Mapp vs. Ohio, and Miranda vs. Arizona require detectives to know what warrants are needed, as well as what type of evidence and statements are or aren't admissible in a court of law.

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