It was about 6:30 on a Friday night in January when Phoenix…
It was about 6:30 on a Friday night in January when Phoenix Police Det. Kemp Layden pulled over a white Jeep Cherokee that was speeding and weaving in and out of its lane. The 47-year-old driver, Harriette Knapp, spoke slowly, her eyes were red and watery, and her pupils were dilated. The inside of the Jeep reeked of marijuana, and Ms. Knapp failed a field sobriety test, which included walking heel-to-toe and standing on one leg. Ms. Knapp told the officer she had smoked marijuana a few hours earlier and taken a prescription sedative the night before. Ms. Knapp passed a portable breath test — she wasn’t drunk. But Layden suspected she was impaired by drugs, which the test can’t detect. A DUI police van equipped with a special chair and table for blood testing pulled up. Ms. Knapp refused to submit to a blood draw. So Layden grabbed his laptop and filled out an electronic warrant, or e-warrant, which was transmitted directly to a judge. The warrant application contained all of the above information. Within 10 minutes, Layden had a search warrant. Another officer drew Ms. Knapp’s blood. A lab report later confirmed she had active THC and a sedative in her blood. Police photographed and fingerprinted Ms. Knapp and issued her a citation for DUI. It took 79 minutes from the time she was stopped until the issuance of the citation. At that point Ms. Knapp was released and she returned to her vehicle to wait for a friend to pick her up to take her home. Her vehicle was about 100 feet from the DUI police van. During the blood draw process Officer Layden gave police dispatch Ms. Knapp’s name. Dispatchers discovered that Ms. Knapp had an outstanding warrant for her arrest and informed Officer Layden. By then Ms. Knapp had already left the DUI police van and was at her vehicle. Officer Layden approached Ms. Knapp and asked her to come back to the DUI police van. He instructed her that she could not leave because he had to arrest her. Ms. Knapp exited the truck and followed Officer Layden back to the DUI police van. Ms. Knapp voluntarily retrieved her purse from the seat of the Jeep when she followed Officer Layden back to the DUI police van. Because the officers were still concluding their investigation, Officer Layden asked Ms. Knapp to sit on a chair outside the DUI police van. Ms. Knapp sat down and placed her purse on the ground next to her. Once Ms. Knapp sat down, Officer Layden moved her purse, which was closed by a zipper, a few feet away from her. At this point Ms. Knapp’s friend arrived to take Ms. Knapp home. Ms. Knapp then asked her friend to take her purse so she would not have to take it to jail. This raised the Officer Layden’s suspicions. When her friend — who was originally willing to take her purse — declined, after being warned by Officer Layden that taking it could be illegal, Ms. Knapp tried to leave it in the Jeep she had been driving. However, Officer Layden refused to let her leave her purse in the Jeep. Officer Layden then asked for her consent to search the purse but she refused. Officer Layden then placed Ms. Knapp in handcuffs behind her back and led her to his nearby patrol car. Officer Layden carried Ms. Knapp’s purse. At the patrol Ms. Knapp stood in front of the hood facing Officer Layden. Officer Layden placed the purse on the hood of his patrol car. At that time, Ms. Knapp stood near the bumper of the patrol car, the purse was on the hood near the windshield (about three to four feet from Ms. Knapp), and Ms. Knapp stood handcuffed facing away from the car and toward Officer Layden. Ms. Knapp’s friend was on the opposite side of the patrol vehicle. Next, after Officer Layden threatened that she would be guilty of a felony for bringing drugs to a detention center, Ms. Knapp told him she was carrying a pistol in her purse. At that point Officer Layden searched the purse and found her pistol. He found no other contraband. When Officer Layden searched the purse, three other officers were present. Ms. Knapp was charged with one count of unlawfully possessing a firearm after a felony conviction in violation of 18 U.S.C. §§ 922(g)(1) and 924(a)(2). She moved to suppress the firearm on Fourth Amendment grounds. The District Court concluded that the entire interaction was valid under Fourth Amendment law and consequently denied the motion to suppress. The Court of Appeals affirmed. The Supreme Court of the United States granted Ms. Knapp’s petition for a writ of certiorari agreeing to review all Fourth Amendment issues presented in the facts and law. You represent either the State or Knapp in the case before the Supreme Court of the United States. You have been assigned to write the brief in support of your client’s position on the constitutionality of all issues you can identify from the above fact pattern.