Oaxaca was identified as the supplier of methamphetamine by several dealers arrested by undercover federal agents. An undercover agent then phoned Oaxaca and set up the pickup of one pound of methamphetamine. A codefendant delivered the methamphetamine to the officers. Officers went to Oaxaca’s home without a warrant to arrest him. They then obtained consent to search from Oaxaca’s sister, and found controlled substances and other evidence in the garage. Because the original entry into the home violated the Fourth Amendment, the consent to search was tainted, and reversal was therefore required. In the absence of exigent circumstances, an arrest warrant must be obtained before the entry into a person’s home to arrest him. Here, there was no warrant, there were no exigent circumstances, and officers entered into Oaxaca’s home before they arrested him. There was no doubt that the subsequent consent to search was the fruit of the Government’s warrantless entry. Because the error in admission of the illegally seized evidence was not harmless beyond a reasonable doubt, reversal was required.