United States, 116 U.S. 616 (1886). In Boyd, a defendant had been compelled to produce his business papers. The Court determined that the compulsory production of those papers amounted to requiring the defendant to provide testimony against himself. The holding in Boyd was limited to the facts in that case. In Bram v. United States, 168 U.S. 532 (1897), the Court held that involuntary confessions were inadmissible. These two early cases stressed the importance of the Fifth Amendment's prohibition against compelled testimony. However, it took a significantly longer period of time for the United States to develop a more comprehensive version of the Exclusionary Rule, and many states had developed their own heightened versions of the Exclusionary Rule prior to that time. Finally, in 1914, the Court developed a comprehensive and strong version of the Exclusionary Rule. In Weeks v. United States, 232 U.S. 383 (1914), the Court held that evidence obtained in violation of the Fourth Amendment was not admissible in Federal court. However, the Weeks rule specifically did not apply in state court proceedings, where most criminal prosecutions actually occur. Therefore, even though the Court had announced a very strong, very comprehensive Exclusionary Rule, it had little impact on most criminal defendants. This remained the rule for a significant period of time. In Wolf v. Colorado, 338 U.S. 25 (1949), the Court determined that states were not required to adopt the Exclusionary Rule. Finally, in 1961, the Court determined that the states were required to adopt the Exclusionary...

In Mapp v. Ohio, 367 U.S. 643 (1961), the Court determined that the Exclusionary Rule had to apply in state court proceedings, not because of the Fourth Amendment or the Fifth Amendment, but because of the Fourteenth Amendment's guarantee of due process.
While the Court was reluctant to extend the Exclusionary Rule to the states, it continued to develop the breadth and scope of the rule in the Federal Courts. By 1920, the Court had officially developed the fruit of the poisonous tree doctrine. In Silverthorne Lumber Co. v. United States, 251 U.S. 385 (1920), the Court first adopted the fruit of the poisonous tree doctrine, which extended inadmissibility beyond evidence collected in direct violation of the Fourth Amendment to evidence that was collected as a result of illegal activity. However, while the Exclusionary Rule can result in the release of a defendant who is known to be factually guilty, there are some limitations on its scope and breadth. The most important limitation is that the Exclusionary Rule only bars the admission of evidence obtained in violation of the defendant's constitutional rights; it does not matter, for purposes of admissibility, if the evidence was obtained in violation of the constitutional rights of another.