The exclusionary rule mentions that evidence must be gathered legally or it can't be used.

The principle based on federal Constitutional Law that evidence illegally seized by law enforcement officers in violation of a suspect's right to be free from unreasonable searches and seizures cannot be used against the suspect in a criminal prosecution.

The exclusionary rule is designed to exclude evidence obtained in violation of a criminal defendant's Fourth Amendment rights. The Fourth Amendment protects against unreasonable searches and seizures by law enforcement personnel. If the search of a criminal suspect is unreasonable, the evidence obtained in the search will be excluded from trial.

The exclusionary rule is a court-made rule. This means that it was created not in statutes passed by legislative bodies but rather by the U.S. Supreme Court. The exclusionary rule applies in federal courts by virtue of the Fourth Amendment. The Court has ruled that it applies in state courts although the due process clause of the Fourteenth Amendment.(The Bill of Rights—the first ten amendments— applies to actions by the federal government. The Fourteenth Amendment, the Court has held, makes most of the protections in the Bill of Rights applicable to actions by the states.)

The exclusionary rule has been in existence since the early 1900s. Before the rule was fashioned, any evidence was admissible in a criminal trial if the judge found the evidence to be relevant. The manner in which the evidence had been seized was not an issue. This began to change in 1914, when the U.S. Supreme Court devised a way to enforce the Fourth Amendment. In Weeks v. United States, 232 U.S. 383, 34 S. Ct. 341, 58 L. Ed. 652 (1914), a federal agent had conducted a warrantless search for evidence of gambling at the home of Fremont Weeks. The evidence seized in the search was used at trial, and Weeks was convicted. On appeal, the Court held that the Fourth Amendment barred the use of evidence secured through a warrantless search. Weeks's conviction was reversed, and thus was born the exclusionary rule.

The best evidence rule concerns limiting potential for alteration. The best evidence rule is a common law rule of evidence which can be traced back at least as far as the 18th century. In Omychund v Barker (1745) 1 Atk, 21, 49; 26 ER 15, 33, Lord Harwicke stated that no evidence was admissible unless it was "the best that the nature of the case will allow". The general rule is that secondary evidence, such as a copy or facsimile, will be not admissible if an original document exists, and is not unavailable due to destruction or other circumstances indicating unavailability.

The rationale for the best evidence rule can be understood from the context in which it arose: in the eighteenth century a copy was usually made by hand by a clerk (or even a litigant). The best evidence rule was predicated on the assumption that, if the original was not produced, there was a significant chance of error or fraud in relying on such a copy.

The hearsay rule concerns computer-generated evidence, which is considered second-hand evidence.

Hearsay is information gathered by one person from another concerning some event, condition, or thing of which the first person had no direct experience. When submitted as evidence, such statements are called hearsay evidence. As a legal term, "hearsay" can also have the narrower meaning of the use of such information as evidence to prove the truth of what is asserted. Such use of "hearsay evidence" in court is generally not allowed. This prohibition is called the hearsay rule.

For example, a witness says "Susan told me Tom was in town". Since the witness did not see Tom in town, the statement would be hearsay evidence to the fact that Tom was in town, and not admissible. However, it would be admissible as evidence that Susan said Tom was in town, and on the issue of her knowledge of whether he was in town.

Hearsay evidence has many exception rules. For the purpose of the exam you must be familiar with the business records exception rule to the Hearsay Evidence. The business records created during the ordinary course of business are considered reliable and can usually be brought in under this exception if the proper foundation is laid when the records are introduced into evidence. Depending on which jurisdiction the case is in, either the records custodian or someone with knowledge of the records must lay a foundation for the records. Logs that are collected as part of a document business process being carried at regular interval would fall under this exception. They could be presented in court and not be considered Hearsay.

Investigation rule is a detractor.

Source: ROTHKE, Ben, CISSP CBK Review presentation on domain 9.

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The FREE Online Law Dictionary at: http://legal-dictionary.thefreedictionary.com/Exclusionary+Rule

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Wikipedia has a nice article on this subject at: http://en.wikipedia.org/wiki/Exclusionary_rule

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http://en.wikipedia.org/wiki/Hearsay_in_United_States_law#Hearsay_exceptions