In the case of Illinois v. Gates, Police received an anonymous letter which provided details about the Gates, a husband and wife, who were trafficking drugs from Florida to Illinois. The letter stated that regularly Mrs. Gates would drive their car down to Florida, the car would be loaded up with drugs, then Mr. Gates would fly down to Florida and drive the car back to Illinois. A detective began to investigate and his observations aligned with many of the details of the anonymous letter; with the assistance of the DEA he observed that Mr. Gates booked a flight to Florida and drove his car back to Illinois the next morning, which was waiting for him in Florida. The detective presented to a judge that the tip was credible on this basis and obtained a search warrant which was used to confiscate drugs and convict Mr. and Mrs. Gates of drug trafficking.
However, the Gates’ attorney argued that the “basis of knowledge” of the anonymous tip was not provided, so the search warrant was not constitutional. Meaning that because the anonymous letter did not state how specifically they knew the information contained the tip could not satisfy the requirements of determining probable cause. The Illinois Supreme Court ruled in favor of the Gates because this argument aligned with previous court cases, specifically those that originally created the Aguilar-Spinelli two-pronged approach to establishing probable cause.
The Aguilar-Spinelli two-pronged approach was the basis for the determination of whether a tip met the standards of probable cause when issuing a search warrant. Under this two-pronged approach, first the source of information had to be proved to be credible and reliable. Second, the tip had to prove to have a reasonable “basis of knowledge,” or show that the information was collected in such a way that the information would not be unreliable. Only if both these prongs were proven independently could it be determined if a tip constituted probable cause to issue a search warrant.
The Supreme Court then heard the Illinois v Gates case in which they specifically addressed the constitutional question of whether issuing a search warrant based on an anonymous tip without an established “basis of knowledge” violates the unwarranted search and seizure clause of the fourth amendment.
The Supreme Court reversed the findings of the Illinois supreme court and described that ‘basis of knowledge” along with credibility/reliability should be used in determining whether probable cause exists, but these should not exist separately as distinct criteria but are connected and should be considered in “totality.” Their decision effectively eliminated the two-pronged test and proved a more flexible and holistic approach to determining probable cause in the granting a search warrant. Rehnquist, the justice who wrote the majority opinion, argued that the determination of probable cause is not the subject of the strict formality required in a trial but is rather simply a determination of whether a reasonable person would find the claim to be probable based upon the evidence. Rehnquist continues that “totality” approach allows judges to more effectively address the needs of both the public and the government. The Aguilar-Spinelli criteria, while important components of determining probable cause, are too inflexible of criteria when both are required independently in determining probable cause.
I agree with the Supreme Court in their decision because reliability and “basis of knowledge” are largely connected so requiring the determination of these separately is an undue burden on judges to determine probable cause and an undue burden on law enforcement’s ability to obtain search warrants. Independently requiring both prongs of Aguilar-Spinelli test is redundant because the “basis of knowledge” is simply another component of determining if the information is reliable, therefore if the “veracity” of the claim can be proven without the “basis of knowledge” it should not be required. It is important to note that the rights granted by the fourth amendment are protections against government search and seizure, but affords no protection from private citizens. Therefore, the “basis of knowledge” does not affect the issuance of a search warrant when information is presented by a private citizen or anonymously. This means specific to the Gates case, even if the anonymous tip stated that the private citizen learned this from entering the Gates property illegally, or searching without consent, the information would still be admissible. Therefore, the “basis of knowledge” prong is only relevant in supporting the overall credibility of the claim, and should not be required outright.
Additionally, in line with the dissenting opinion, I agree this decision does create the possibility for abuse but I do not believe this argument outweighs the arguments of the majority. The dissenting opinion was concerned with the ability of law enforcement to use relaxed criteria for determining probable cause to ascertain search warrants with questionable or dishonest sources of information. However, when constrained to the specific question of the role of anonymous tips, or even tips from private citizens, there is no conflict. The only source of conflict is the constraints placed on government officials from unwarranted search and seizure, however, police abuse of this ruling is constrained by our perjury laws so keeping the Aguilar-Spinelli test for that reason alone is redundant. Police could illegally gather information then attempt to pass the information off as a “tip” but that is already protected by our perjury laws so this case should not be decided simply on that basis.