2. Techniques of Investigation


The facts of a given case will usually dictate how it is investigated.  Some cases begin as others end.  For example, a defendant in one case, as part of a plea agreement or pursuant to a grant of immunity, may implicate another person or persons, which in turn, will result in a new investigation being commenced in order to corroborate and/or confirm the information provided.  An AUSA, with the concurrence of the U.S. Attorney and/or the Attorney General of the United States, has the discretion to plea bargain with criminal subjects and also has the authority to apply for and obtain immunity from prosecution for given witnesses.   Such discretion has been used on countless occasions throughout the United States to either begin an investigation or strengthen one already in process.  Such power, available to a federal prosecutor, is a technique often employed to further the investigation of an alleged federal crime.

The techniques of federal investigation are myriad and almost limitless.  Surveillance of certain subjects may be employed by the investigative agency, informants may be utilized, and records may be subpoenaed.  Electronic surveillance and wiretaps, under limited circumstances and only with prior judicial approval, may also be utilized.  Consensual tape recordings may occur.  Search warrants may be utilized and painstaking forensic analyses of evidence employed.  The utilization of all such techniques will be employed for the same purpose: to discover the truth and to prosecute those who violate federal law.

To familiarize the reader with the applicability of some of the more common techniques of investigation utilized by federal investigators, a brief discussion of the techniques themselves will probably be helpful at this point in our discussion.

(a)        Surveillance

This technique is usually employed where photographic evidence may greatly assist in the investigation of the case.   If an informant alleges that certain persons sell drugs at certain locations at certain times, and if such areas are capable of being secretly photographed, surveillance may likely be employed as an investigative technique.  If a cooperating witness alleges that money will change hands at a certain time and place, if such information is corroborated through surveillance and photos, this is strong evidence of corroboration of the information supplied by the witness.  Sometimes visual surveillance may be employed by a federal investigator just to determine with whom a suspect associates with and where he goes during certain times of the day.  If the case agent has a tip that the suspect will conduct a transaction at a certain time and place, and this is confirmed through surveillance of the subject, valuable evidence and information may come to light as a result of such efforts.  Again, the facts of a given case will dictate whether this particular investigative technique is likely to be employed.

(b)        Mail Covers

This investigative technique, perfectly legal, is little known to the public and oftentimes very useful to the investigating agency.  A mail cover is an analysis of the public aspects of a given person’s mail by the United States Postal Service.  While it would be illegal for the Postal Service to open a person’s mail without a court authorized search warrant, there is nothing illegal in examining what is open and public about correspondence dispatched through the United States mails.  As might be imagined, much can be learned from examining a person’s incoming and outgoing mail.  The federal agent can learn who the suspect corresponds with from the return addresses on the outside of envelopes.  He can learn where he receives bills from and where he likely conducts his banking activities. By examining the postmarks on a suspect’s relatives’ mail, an agent may even discover where a fugitive is hiding or where a suspect is likely located.

The Fourth Amendment of the United States Constitution protects all citizens from unwarranted government intrusion into their privacy.  The personal contents of mail are certainly private by definition and therefore constitutionally protected.  However, such information that is made available to the public and is observable with the naked eye without any intrusion into private contents is not constitutionally protected.  However, to guard against abuse of this technique, the Postal Service will agree to monitor a given subject’s mail only upon official request of an AUSA and only after receipt of official verification that such information is necessary to properly enforce federal law.

(c)        Wiretaps

Most laypersons believe that telephone wiretaps are commonly utilized by federal investigative agencies.  However, because of the Orwellian nature of this powerful investigative tool, it can only legally be used under very narrow circumstances; specifically, after personal approval by the Attorney General of the United States (or his designee) and approval by a United States District Court Judge. Because of the very rigid laws governing the use of this technique, wiretaps are in actuality sparingly employed and properly utilized only after all other available techniques of investigation have failed.

Technology in the field of telecommunications has changed the world we live in.  Simply by dialing a number on our telephone, we can communicate with people next door, in an adjoining state, across the country, or around the globe.  The same technology that brought us this wondrous capability has also brought the specter of “Big Brother” intrusion into our private lives.  In recognition of the fact that such technology, if improperly applied, could threaten cherished constitutional rights of privacy as protected by the Fourth Amendment, the Congress of the United States passed far reaching legislation in 1968 specifically governing the permissible uses of such technology.  This legislation, a part of the Omnibus Crime Control Act of 1968, protects Americans from eavesdropping, not only from unscrupulous individuals, but also from an overzealous government.  The provisions of this Act make it illegal for any person to electronically eavesdrop private telephone conversations except under very narrow circumstances. Because both the government and individuals are restricted in the use of such technology by this legislation, theoretically, Big Brother can never rise in the United States through this means.

The principal statutory provisions governing the wire interception of oral communications are found in Title 18 U.S.C. §2510 et. seq.  Not only do these laws make it illegal for any person to electronically eavesdrop on private communications absent court approval, they even go so far as to prohibit the manufacture and/or possession of eavesdropping equipment, again, except under very narrow circumstances.  Criminal penalties are provided for illegal eavesdropping, possession of eavesdropping equipment, and for the disclosure of intercepted conversations.

While cognizant of the dangers of such technology, Congress recognized that when applied for the salutary purpose of fighting crime, electronic eavesdropping could be a powerful force for good. Thus, even though it is illegal to electronically intercept the private conversations of others in the United States, it is not necessarily illegal for law enforcement personnel to do so, provided that the laws permitting the utilization of such investigative measures is strictly adhered to.

To acquaint the reader with the very strict requirements governing the use of this technology by law enforcement officials, the authors suggest reading Title 18 U.S.C. §2518 entitled “Procedure of Interception of Wire, Oral or Electronic Communications”.

As stated above, not only is court authorization required before electronic eavesdropping may commence, the Attorney General of the United States (or his designee) must first approve of the application to the court for the necessary judicial approval.  No such application can even be considered unless the conduct being investigated is one of the more serious crimes designated by Congress as warranting the use of this technique.  See generally Title 18 U.S.C. §2516.

The courts are extremely cautious in their review of wiretap applications.  Only if compelling and legitimate law enforcing objectives justify the use of this technique will judicial approval likely be obtained.  If the authority of the court is exceeded or abused, criminal and civil penalties are available to punish the transgressor.  On the other hand, if the law is complied with and circumstances warrant it, federal law enforcement agencies can effectively utilize this investigative technique to combat crime.

(d)        Consensual Monitoring

The Fourth Amendment of the United States Constitution protects against “unreasonable” invasions by the Government of protected privacy interests. However, the courts have specifically held that the Fourth Amendment affords no protection against consensual monitoring of conversations by a participant thereto. In every conversation we have with another person, however private the information we may share, it is quite possible for the person we share such information with to disclose it to third parties. This is the chance we take when we voluntarily choose to disclose private information to another person.  Because there is no law, which prohibits the disclosure of non-privileged information by third parties, we run the risk of such disclosures when we decide to communicate. Accordingly, since a participant to a conversation may always legally disclose its contents to anyone he chooses, the courts have held that there is nothing wrong if that person chooses to tape record such conversations and disclose the communication verbatim.

We have learned that third parties may not intrude upon private conversations by means of electronic eavesdropping. However, there is no intrusion upon the privacy of such a conversation by an unwanted third party if one of the participants to the conversation decides to share it with others.  If you consent to talk to your best friend, you take your chances whether he will choose to disclose all you tell him to other parties.  The courts have held, therefore, that if your neighbor tape-records the conversation he has with you, that such conduct is legal.  Why?  Because there is no intrusion by a third party into a private domain.  Instead, a participant to the conversation consents himself to its being recorded.  As long as such consent is voluntarily given by a participant to a conversation, the courts feel there can never be an illegal intrusion upon a reasonable expectation of privacy.  This is because, under the First Amendment, we have the right to tell anyone we wish what we know unless the information we communicate happens to be legally privileged.

The law recognizes several classifications of privileged communications.  Conversations between attorneys and their clients are privileged.  Conversations between married persons are privileged.  Conversations between a psychiatrist and his patient are privileged.  The contents of these and other privileged communications cannot be disclosed without the express consent of the party holding the privilege – i.e. – the client, the patient or the confiding spouse.  However, as to non-privileged conversations, there is no barred public dissemination of whatever we may learn from others.

If you wish to consensually tape record a telephone conversation you have with another, you may properly do so under federal law.  If you wish to share this information with others, such as law enforcement personnel, this is proper as well.  Moreover, if you agree to consensually record a conversation with another at the behest of government investigators, this is legal also.  In short, participants to a private conversation have the prerogative to divulge what they learn in the conversation to anyone they deem appropriate.  They also have the right to surreptitiously record the conversation without the knowledge or approval of the other participant(s).  Under federal law, as long as one participant to a conversation voluntarily consents, recordings may be made and information revealed.

Needless to say, the application of this technique in the investigation of federal crime can be extremely efficacious in the prosecution of a case.  The defendant’s own voice may ultimately provide the most damaging information in a case if incriminating statements are made in a conversation.  Thus, it is not uncommon at all for federal investigators to utilize this investigative technique.  Often, an agent may record such a conversation himself while acting in an undercover capacity.  Agents also routinely ask cooperating witnesses and informants to tape record their conversations with subjects of federal investigation.  Again, so long as a participant to the tape-recorded conversation consents, the evidence will be admissible in court.

(e)        Search Warrants

If a federal agent has probable cause to believe that evidence of a crime may be found at a particular location where legitimate expectations of privacy exist, he may not intrude upon this privacy or enter the place unless he is authorized to do so by warrant or by someone with apparent authority to consent to such a search. Accordingly, in a typical case where such probable cause exists, the agent will apply for a search warrant to authorize seizure of the suspected evidence.

The Fourth Amendment of the United States Constitution protects against unreasonable searches and seizure by the government.  By definition, any search not supported by a good faith probable cause belief is unreasonable.  The courts have held that a presumption exists that warrantless searches are unreasonable. While there are many recognized exceptions to this rule, all involving situations where legitimate expectations of privacy do not exist, or are outweighed by exigent circumstances, nonetheless, a federal agent must always be cognizant of the Fourth Amendment if he is contemplating conducting a search or making a seizure of evidence.

If in a hypothetical bank robbery case, the federal agent in charge of the case receives reliable information concerning the whereabouts of the stolen money, and if it turns out that the money is alleged to be hidden in a private residence, in order to legally enter that residence and conduct a search, the agent must first apply to the court for a search warrant.  Such application will be denied unless it is made under oath and unless probable cause is established to the satisfaction of the court.  In other words, only if the agent presents the court with reliable information, which indicates that there is probable cause to believe that evidence of a crime is located where the agent wishes to search, will he be given judicial authority to look for it.  Because the Fourth Amendment is a cherished Constitutional right, the courts require that probable cause be established by way of affidavit before allowing government intrusion upon private property.

Rule 41 of the Federal Rules of Criminal Procedure sets forth the procedure in federal courts that governs whether a federal investigator can obtain a search warrant and, how it must be executed if one is obtained.  The provisions of this rule are clear and succinct and are largely self-explanatory.

If an agent can lawfully gain access to evidence of a crime without application for a search warrant, it can be reasonably expected that he will do so.   In those cases where no legal exception to the warrant requirement exists, however, this investigative technique is the only proper way to seize contraband and/or evidence of a crime.  Because the courts seek to encourage compliance with and appreciation of the Fourth Amendment’s requirements by law enforcement personnel, if a search is illegally conducted, all evidence obtained thereby will be excluded from evidence and suppressed.  Thus, because agents know that evidence illegally obtained will be excluded and suppressed by the courts, they are encouraged to comply with the Fourth Amendment’s requirements.

Next Section: C. Implementation of Policy

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