Lesson 1    



The World of the Private Investigator 

As you read this lesson, be prepared to answer the following questions:

1.      What are the five major types of investigators practicing in today's investigative marketplace?

2.      What is the formal definition of an investigator?

3.      What are the differences between law enforcement, private investigation, and guard & patrol services?

4.      What are the powers and responsibilities of the private investigator, and how can he avoid abusing his power?

5.      What dangers and risks do private investigators face?

6.      When do private investigators carry guns?

7.      What new roles do women play in private investigation, and why are their services valued?

8.      What attributes and skills contribute to the success of the private investigator?

9.      How are investigative achievements and experience recognized?

10.  What terms are applicable to private investigation?

11.  How can you determine your investigative interests and make maximum use of your skills and talents in the investigative profession?

12.  What is the common denominator in all areas of private investigation?


Private investigation is an easy profession to get into at any age and at any level of your career development. The young and inexperienced will most probably start out as a field investigator in a detective agency and enjoy trying out various sneaky and devious movements, while remaining fundamentally honest and knowing clearly the difference between right and wrong. They will combine luck, with common sense and "street smarts," in order to get results. They will get plenty of practice thinking on their feet, looking over their shoulders, and coming up with fast, ready answers if "caught in the middle of something." The young and inexperienced will find many years of challenging work and, with hard work and persistence, be able to make the many career transitions that lead to success and financial security.

Middle-aged individuals making a mid-life career change will find that private investigation offers an ideal next profession. These folks have cultivated a genuine interest in people and usually know the various human problems and motives. Because of their experience and maturity, they are able to deal with varying, often unpredictable circumstances. Further, middle-aged individuals usually enter the profession with a wide range of experience and knowledge concerning the professional and technical matters of life in general and by nature are a curious type who enjoy digging up all sorts of information from a number of sources. These qualities are ideal for private investigation. And, since the work is so varied, they can focus on the aspects of private investigation that fit their mental, physical and educational level.

The third group, ex-law enforcement officials, make the transition easily. The only difficulty they may have is adjusting to the new investigative format for a variety of new civil and business investigations that were not a part of their previous official responsibilities. They bring with them the cultivated "official" demeanor and find new challenge in running their own detective agencies as a business, as opposed to being a civil service employee.

For all three categories, learning private investigation does not require a college education or formal law enforcement training, although the latter can be helpful. It only requires knowing the procedures, the skills, and investigative techniques. That's what this course provides you, in full! Further, the profession is fun and exciting to learn. By taking DTI's training course you will learn the skills and techniques necessary to function as a qualified investigator. Just follow the road maps throughout your course and you will find your lessons interesting and very informative.

This first lesson contains some very important introductory topics which will provide you perspective and direction. We begin by defining and describing different types of private investigators, and compare them to law enforcement and guard & patrol services. We then discuss issues of power and responsibility as they relate to the professional investigator; we place great emphasis on maintaining a high level of integrity and character. We go on to explore the dangers and risks in private investigation and the issues concerning the use of guns. Following that, is a consideration of the different certification programs available, as well as other means to increase your professional standing. Then, we discuss the expanded opportunities for women in private investigation, and the attributes of investigators who perform well. Finally, we review the terms applicable to private investigation and offer guidance on how to maximize your talents by determining your investigative interest.

As you will see as you move through the course, private investigation is a challenging adventure that combines human nature, trickery, logic, physical skill, keen observation and accumulating facts and evidence. That's an exciting combination, and the profession is well worth your time and effort. So   without further introduction — let's begin!

Types of Investigators

Before we formally define the term private investigator and discuss his duties, let's take a look at the types of investigators in practice today. This brief view should give you perspective on the tremendous variety of working assignments available. Five major types are discussed here. Note that some investigative tasks may overlap, yet each type has its unique purpose.

General Investigator

This investigator has a multitude of different clients — small businesses, corporations, retail establishments and individuals. For these clients he performs many and varied services, including location of missing persons, pre-employment background checks, internal theft investigations, undercover investigations, surveillance, process serving and electronic security counter measures. No list of assignments can exhaust all possible potentialities; new situations requiring new approaches develop constantly. One of the realities for general investigations is the persistence of such variables, making every case and technique unique. The variability springs from the nature of human need and from the conflicts and complexities of our changing society.

Legal Investigators

This investigator is usually employed by law firms handling mostly personal injury cases. A legal investigator's responsibility involves accumulating and assembling facts so an attorney can intelligently apply the law in the best interests of his client. The legal investigator mainly interviews prospective witnesses and experts used in the litigation. He also searches out testimonial, documentary and physical evidence. In defense of criminal cases, the legal investigator protects the accused of his constitutional rights. Finally, legal investigators frequently testify in court.

The nature of legal investigations varies considerably with the area of law involved. Negligence cases, for example, require a great deal of investigative work. Damaged vehicles, defective machines, and injured persons all have to be examined. Witnesses have to be interviewed at length in order to determine the extent of negligence. In worker's compensation cases, negligence is not an issue, but the extent of injury is. Likewise, the extent to which an injury was work related becomes an important aspect of the investigation. In probate, an investigation could involve either locating missing heirs or attempting to determine what the mental state of the deceased was at the time the will was written. The underlying investigative skills in all areas are basically the same.

Insurance Investigators

These professionals are either employed directly by insurance companies, or are subcontracted by them. Insurance investigators perform the same basic functions as legal investigators, but their goal is to defend the insurance companies against fraudulent claims. Their duties include investigating cases involving arson, product liability, workmen's compensation and personal injury, as well as medical malpractice.

Corporate Investigators and Industrial Security

Many large corporations and businesses hire from within their own security forces to investigate internal matters. The most common investigations are pre-employment checks, internal theft, falsifying records, accidents, workmen's compensation, and lawsuits.

These investigators also develop and administer internal programs to investigate many crimes, such as pirating, trade secrets and shoplifting. They are also responsible for minimizing losses from natural and man-made disasters. These investigators focus on general security functions common to most types of organizations, such as physical security, disaster planning, computer security, protecting proprietary information, fire prevention and terrorism. A new type of security investigator concentrates on security concerns of specific organizations, such as government installations, retailers, financial institutions, heath care facilities and energy firms.

Specialized Related Fields

Many investigators also perform auto repossessions, bounty hunting, bodyguard and security work, all fields related to private investigation. Many of the techniques used in these specialized related fields are the same as those used in primary private investigation. However, the range of skill and actual fact-finding tasks are limited. Private investigators, with interest in these areas, usually work in these specialized related fields as a secondary business through their main investigative business.

Definitions of Private Investigators

We have already seen that the functions of investigation are many and multi-faceted. Now, let's get a bit technical and nail down a formal definition. From its Latin derivative, vestigare, investigation implies a tracking, a search, an assimilation, or collection of information and facts. This essential function is common to al types of investigations, regardless of their special purposes. The following definitions of two of the major types discussed above further amplify the general definition and provide more detail.

General Investigator

The statues in many states have generally defined the private investigator as "any person who engages in the business of, or accepts employment to make investigations to determine information of crimes or civil wrongs, the location, disposition, or recovery of stolen property; the cause of accidents, fires, damages or injury to persons or to property; or evidence to be used before any court, board, officer, or investigative committee."

Private investigation can also be defined as the process of fact assimilation. It is the systematic collection of evidence necessary to support or refute a claim, whether it be civil or criminal in nature. Private investigation is the process of observation, close inspection and analysis, as well as the continuous and regular inquiry into a specific subject. Private investigation is the search and journey toward the reconstruction of events and conditions pertinent to a clients needs and interest. It is the collection of information to resolve factual disputes and confusing data. It can also be the supplying of independent pieces of information, such as names, addresses and telephone numbers.

Legal Investigator

A legal investigator is trained in techniques of fact finding and forensic procedures (applying scientific and medical knowledge to legal matters for formal argumentation in law court). He is committed to the pursuit of truth because it is only by having verified facts at hand that an attorney can intelligently apply the law in the best interest of his client. As we saw earlier, his aim is to assemble as complete a factual picture of a situation as possible so that a case can be prepared for trial.

Legal investigations differ from general investigations in that they include the following uniform practices:

1.      A logical investigative or procedural sequence must be followed.

2.      Real, physical evidence must be legally obtained.

3.      Real, physical evidence must be properly stored and preserved.

4.      Witnesses must be identified, interviewed and prepared for any potential or actual litigation.

5.      Reports and documentation must be collected.

6.      Information must be accurately and completely recorded.

7.      Evidence collected must correlate to the claim, cause of action, or offense charged.

Comparing Law Enforcement, Private Investigation, and Guard and Patrol Service

Since law enforcement, private investigation, and guard & patrol service are related, there could be some confusion in understanding the similarities and differences among them. Let's briefly distinguish their functions so we may obtain a better understanding of private investigation.

Law Enforcement

Law enforcement agencies are public agencies paid for by citizen's taxes. A police investigation is conducted basically for the purpose of apprehending a suspect of a crime and locating evidence for a successful prosecution of a case. The police use three main sources to reconstruct the past, as well as to identify and apprehend suspects: people, records and evidence.

Private Investigations

Private investigation agencies, on the other hand, are hired by a variety of clients, such as banks, hotels, insurance companies, stores, lawyers, manufacturers, individuals, etc. for varying purposes including:

1.      To determine if there is sufficient factual evidence to support or defeat each element of a cause of action or a case at trial, such as workmen's comp, insurance fraud, medical malpractice, criminal or civil cases, etc.

2.      To locate persons or property.

3.      To investigate frauds, embezzlements, divorces, employee thefts, etc.

4.      To conduct background checks, surveillances, asset checks, interviews, undercover, etc.

Guard and Patrol Services

Guard and patrol personnel offer their services to industrial plants, financial institutions, educational institutions, retail establishments, hotels, health care facilities, recreation facilities, libraries and museums, warehouse and goods distribution depots, etc. They undertake the following responsibilities:

1.      Prevention and detection of intrusion, unauthorized entry or activity, vandalism, or trespass on private property.

2.      Prevention and detection of theft, loss, embezzlement, misappropriation or concealment of merchandise, or other valuable documents or papers.

3.      Control, regulation, or direction of the flow or movements of the public, whether by vehicle or otherwise to assume the protection of property.

4.      Protection of individuals from bodily harm.

5.      Enforcement of rules, regulations and policy related to crime reductions.

Power and Responsibility of Being a Private Investigator

New private investigators learn certain confidential techniques that give them power and ability over the average citizen. They must, therefore, adhere to a higher level of responsibility and ethics. Some of the skills a new investigator learns could result in a misuse of power. They are:

·         Determining a person's true identity

·         Determining an individual's personal background

·         Determine a person's current employment

·         Determining someone's personal and professional reputation

·         Determining a person's bank balances, debt level and financial background

·         Determining a person's unlisted telephone number

Learning to become a private investigator also entails learning confidential techniques to move smoothly and swiftly through any bureaucratic system. Investigators know how to avoid certain restrictions that normally prevent access by the average citizen.

But gaining a higher level of power and professional ability must be balanced with a higher level of responsibility. In few other businesses or professions is one expected to maintain the high standards of integrity as one needs as an investigator. An investigator must possess good moral character and be exemplary in conduct, honesty, and loyal to the profession.

Danger and Risks in Private Investigation

Some aspects of private investigation have no inherent danger or risk. These include searching public records, pre-trial preparation for civil actions, computer crime investigations, etc. But, many other aspects of private investigation do involve danger and risk. There are two types of danger: expected and unexpected. When investigators can anticipate a high probability of danger, then the danger is expected. Examples include: criminal investigation, employee theft, undercover investigation, process serving, marital investigations, surveillance, and bodyguard work. Unexpected danger on the other hand is unforeseeable and uncontrollable. Examples include an ambush or assault when you least expect it.

Risk, on the other hand, is the voluntary taking of a dangerous chance. For example, an investigator on surveillance risks the hazards of running a red light because he does not want to lose the subject. Risk in this case is taken under conditions of uncertainty (possible auto collision) which exposes the investigator to possible loss in order to reach a desired outcome (maintaining surveillance on the subject). Investigators take certain risks because they strive for some benefit or professional compensation.

From the psychological standpoint, the exposure to risk and danger itself appeals to many individuals. Many private investigators, as well as those in related fields such as law enforcement, get as must satisfaction from knowing that they face constant danger. However, it is not the harm or danger they value, but the heightened intensity which comes from the exposure and the added challenge of keeping it from happening. In other words, many investigators thrive on the adrenaline rush. Those who enjoy the risks and dangers of private investigation do not envision themselves as taking outrageous chances. Rather, they prefer to see danger as an intense stimulant to overcome challenging assignments.

Carrying a Gun

As a general rule, private investigators do not carry guns. Movies and detective television series feed on fantasies of private eyes that pack guns and beat the truth out of the bad guys. This is far from the truth. The private investigator's work consists of cases that do not involve street arrests or dealing with violent criminals. That job belongs to the police. However, in some circumstances, private investigators do need to carry guns, at times, after obtaining a weapons permit from their local Sheriff's department. These incidents include bodyguard assignments, protecting evidence, organized crime cases, or when there is a direct threat on an investigator's life.

From a psychological standpoint, carrying a gun can give a private investigator a distorted sense of power. The transformation from an anonymous civilian to a private investigator can create the illusion of power and superiority, which can have a profound impact on the investigator's self concept. He can mistakenly regard himself more capable, stronger and smarter than others. Carrying a gun makes him think he is the person he's dreamed of becoming, thus gratifying childhood fantasies of omnipotence. Such feelings can become addictive, since power and authority are important vehicles to pleasure. Eventually, the private investigator cannot resist his addiction. After all, the opposite feelings are powerlessness and fear, which reinforce the need to carry a weapon. The well-balanced private investigator is aware of this power temptation and balances it with good judgment, emotional maturity and moderation, and finds no need to carry a gun except in certain situations.

Women in Private Investigation

The private investigation profession may have been marked as a man's domain in the past, but that image is beginning to change. The number of women in the field, while still substantially smaller than the number of men, is rising rapidly.

The days of the tough, ex-cop, bourbon in the desk drawer and carrying a .45 gun, are over. Today, "data detectives" are becoming far more prevalent than the traditional tough, two-fisted PI. Women do an exceptional job in researching court documents, using computers, gathering data, etc. Women are also effective as "people detectives," skills very much in demand. They do an exemplary job of interviewing clients and thus have a much better chance of obtaining information from people than their male counterparts. People are usually suspicious and apprehensive of a male investigator, but when they interact with a female investigator, they don't feel as threatened. People also tend to relax when a woman is on the phone. It is much easier for a woman to use a telephone pretext for obtaining information than it is for her male counterpart. Even on surveillances, a female detective is less likely to arouse suspicion or apprehension in a subject. This is especially true when the subject is a woman who frequently fears the possibility of being stalked or assaulted by a man. Even when a female investigator follows a male subject, he is less likely to become suspicious of her presence. This increases the probability of success.

If you are a male trainee who plans to start your own agency, DTI recommends teaming up with a female agent, wife, girlfriend, or associate. You will have a much higher chance of success as a male/female team than if you work individually or in an all-male environment. If you are a female and training to become a detective, your opportunities are unlimited. You can easily get a job in a detective agency or work easily with a male counterpart as a two person team, especially after becoming a DTI graduate.

Many medium size detective agencies tend to hire more women today than in the past. They find that they are more dedicated and conscientious. In one detective agency, for example, for every twelve investigators hired, eight are women.

Private Investigators
Who Perform Well

Many studies show the personal attributes and professional skills necessary for success. They provide a mechanism for measuring traits that can help you evaluate yourself at any point in your career. By reviewing the following list, you can get valuable feedback as to your current strengths and weaknesses. Here's what you should look for in yourself:

Intelligence and reasoning ability

Can you analyze and integrate many facts into a plan or report? Can you use facts to draw conclusions?

Curiosity and imagination

Are you driven to hunt down all pertinent facts and clues, taking nothing for granted? Are you skeptical of the obvious? Do you have a sense for the unusual? Can you tell when something is out of place or not in keeping with the norm? Are you suspicious enough about human nature to keep digging for better answers? Are you fully aware of your surroundings so that you notice small things that may offer clues?

Observation and memory

Are all five senses intact and functioning (sight, hearing, touch, smell, taste)? Are you alert and attentive?

Knowledge of life and people

Can you deal with people from all walks of life, minorities, inner-city residents, suburban dwellers, the young, the old? Do you have common sense, an outgoing personality, a spirit of cooperation, emotional stability, and acting ability for role playing?

Technical know-how

Can you use technical equipment (cameras, videos, computers, etc.) in your investigations to gather facts or document activities?

Perseverance, stick-to-itiveness, and energy

Many who wish to become private investigators believe the job involves a glamorous lifestyle. But, the ability not to tire easily, survive boredom, and keep energy in reserve in order to carry on is more realistic. Do you have those qualities?

Recognize and control bias and prejudice in oneself and on the job

Can you acknowledge your own biases and balance them with the truth in order to maintain objectivity? 

Sensitivity to people's feelings

Can you act with discretion and tack? Do you respect a confidence?

Honesty and courage to withstand temptation and corruption

Can you "just say no" to a bribe? Can you avoid an emotional involvement with a client, even if the temptation is strong?

Ability to testify in court

Are you familiar with the rules of evidence and the pitfalls of cross-examination? Can you maintain sincerity as a witness and state facts impartially so you are credible?

Communications skills

Can you speak effectively to people? Are you a good listener? Can you use public relations skills to "sell" yourself? Does your physical appearance communicate professionalism and confidence?

Passion and purpose

Do you have a burning desire to learn and become a private investigator? Do you feel a deep purpose and meaning in entering the private investigation field? Have you always thought that you would make a good PI?

No doubt you did very well on some items, and perhaps not so well on others. Your strengths will give you an advantage immediately. Your weaknesses can easily be overcome with study and practice. That's what this course is all about.


Private investigation, like other professions, has levels of achievement and recognition based upon experience. This achievement is recognized through certification, the purpose of which is to establish a professionally recognized standard. Certification provides special recognition of performance and investigative skill development that attests to your years of experience as a private investigator.

Included in this illustration is a business card of a private investigator operating in California. (Sorry, only viewable in PDF file format)


Notice after his name are the initials "CPP, CFE, CPI." These stand for "American Society for Industrial Security, National Association of Fraud Examiners, and Certified Professional Investigator." There are approximately twelve to fifteen professional certification programs available to experienced investigators as they proceed through their careers. The requirements for certification vary from program to program. Generally, the investigator must have two years work experience as a full time investigator. The programs require you to take a written and oral examination. Some require that you complete an accredited college, school or training program, such as DTI. Other certification programs require that you prepare a paper of at least 1000 words on any investigative subject.

Terms Applicable to Private Investigation

The following terms are used throughout your course. These terms are specifically relevant to the aspects of conducting work or assignments.


In this course you will develop many new skills that will increase your ability to investigate a wide range of cases. Skills are something you learn to do. They are competencies that you will develop as a result of training, experience, and/or education.

Investigative Technique

Investigative technique is the process of combining many investigative skills in carrying out an assignment. Some investigations only require using one investigative technique, such as surveillance, while other assignments require multiple techniques, such as conducting a surveillance, then conducting a telephone pretext call, then using video equipment to document the incident.


This is the actual undertaking of the assignment involving labor or difficulty. It does not necessarily involve skill, or investigative technique.


Knowledge provides awareness, familiarity, and understanding of such things as laws, crimes, equipment, tricks of the trade, etc., that will increase your well rounded awareness of private investigation.

Procedural Steps

Many investigations, such as legal investigations, insurance investigations, missing persons investigations, fraud investigations, etc., require a particular course of action or sequential steps to follow to complete the assignment. It is the established way of carrying out assignments. The procedural steps may require using your skill, investigative technique, knowledge, or a combination of all three. Many investigations are inherently complex. Some procedural steps cannot be executed until other steps have been completed first, or carried out in parallel. Should the procedures be out of sync with each other, the whole investigation may be jeopardized. Pay particular attention to the procedural steps outlined in your training course. This is the backbone of conducting all investigations.

Assignments—Also Known as Investigations or Cases

The whole investigative assignment process begins when a client has a need to fulfill. The need may be to investigate an internal theft, conduct a background check, find a missing person, or obtain an unlisted telephone number. Assignments are directed at achieving specific results. They can be simple and entail carrying out only one activity, or complex, entailing many related activities. An assignment is a system--that is, a whole made up of interrelated parts, or procedural steps. Assignments are undertaken in a finite period of time. They are temporary. They have reasonably well defined beginnings, middles, and ends. When the assignment goals are achieved, the assignment ends. While many assignments may be similar, each is, to a degree, a one-of-a-kind undertaking.


Investigative talents are natural capabilities — or appear to be. It's possible to describe one or another investigator as having a talent for surveillance, or a "nose" for facts, or an uncanny ability to use equipment. In most cases, the talent is actually maximized through learning and practice. You can maximize your talents by developing investigative skills around them. You will find that the more you use your talents, the easier your work will be.

A major obstacle to developing your talents is unnecessarily struggling through every case in the false belief that you are the only one having this difficulty.


You can let go of the struggle by believing that the investigative problems you constantly face are the norm, and are present in every detective agency and faced by every investigator.

As you progress through your course, determine your likes and dislikes and what skills seem to come easily to you. These are the ones which will naturally develop into talent, and will eventually lead to expertise in that particular area of investigation.

Determining Your Investigative Interests

As you proceed through your training, you will learn how to investigate many different assignments. You will also be exposed to many investigative techniques, technological equipment and skills used by today's professionals. This process will give you a chance to determine your likes and dislikes, as well as your strengths, weakness, talents, and skills. Some students show talent in surveillance, following people, and employing trickery. Others develop talent using telephone pretexts, interviewing subjects, finding missing persons, and skip tracing. Many also like working for insurance companies, or investigating workmen's comp cases, since the work is consistent and steady. Retired or ex-law enforcement students like dealing with the criminal aspect of private investigation — internal theft, narcotics, arson, fraud — and make good witnesses since they have years of experience testifying in court. Or, you may enjoy working with attorneys in pre-trial preparation. This course will help you decide your own special interests and where you would most like to work — in a corporation, an insurance company, an investigative agency, or independently.

But, no matter what area or combination of areas where your strengths and interests lie, there is one absolutely necessary common denominator for the entire detective profession: private investigators collect factual information. Without information, there are no cases, and there is no success. Investigators obtain information from three main sources — people, records, and physical evidence. And, they use a variety of investigative techniques, procedural steps, confidential sources and equipment to assist in its gathering. The process is fascinating, as the assembling of information ultimately leads to the successful conclusion of cases.

As you proceed through your DTI training, pay close attention to the "Records Used In...". These are condensed outlines of the procedural steps for specific investigations. And, as you learn about these procedural steps, investigative techniques, and equipment, ask yourself, "What information can be obtained using these methods?" By the end of your training you will have developed professionally to the point where you can work very effectively as a new private investigator. You will know how to obtain information on any incident, person, or past event by paying close attention to the techniques you learn in this course.

You are about to begin a most challenging, gratifying chapter in your professional life. We wish you good luck, and look forward to the day when you can proudly say you have completed DTI's training and are ready to begin your new career.


This introductory lesson has offered you a comprehensive overview of the investigative profession. You have discovered the definitions and types of private investigators, and have learned the differences between them and other related professions, such as law enforcement and guard & patrol services. You have also learned about the nature of power and responsibility assumed by private investigators. We especially emphasized maintaining a very high level of integrity and character to avoid abusing power. You learned about the dangers and risks that are part of the investigative profession, and how they are often a stimulus for excitement for some investigators. Issues concerning use of guns by investigators was also explored.

We then went on to discuss certification and its value to establishing your credentials, and offered guidance on how you can advance professionally. The increasing prominence of women as investigators was explored, as well as their value to agencies and investigative teams. We reviewed some terms applicable to private investigation, and concluded with a brief discussion on determining your investigative interests.

If you believe you have mastered the instruction in this lesson, turn to the next page for the Progress Check.


Remember, you only receive Lesson 1, with no Progress Check or Official Exam. Because of space limitations, you will not receive the other training components   Road Maps, Course Introduction, Equipment Catalog, Special Topics, Resource Documents, Detective Field Exercises, and Crimes and Puzzlements, totaling over 213 pages that you will receive in your first study unit when you enroll. 

We hope that you have experienced the high quality training that DTI delivers in the Master Detective Course. You may now return to DTI’s website to continue your researrch.