Calling Out Maryland v. King: DNA, Cell Phones, and the Fourth Amendment

45 Pages Posted: 24 Jan 2015

See all articles by Jennie Silk

Jennie Silk

University of Mississippi - School of Law

Date Written: January 21, 2015


In Maryland v. King, the Supreme Court narrowly upheld a Maryland statute that permits police to obtain a DNA sample from an arrestee without a search warrant. A year later, the Court drastically changed course and provided significantly more protection to an arrestee’s privacy. In a unanimous decision, the Court in Riley v. California held that police must obtain a search warrant before they can search the cell phone of an arrestee.

This article is the first to compare the Court’s conflicting decisions in Riley and King. Riley and King present the same issue: governmental invasion of privacy for purposes of general crime solving. The Court in King refused to admit that the true purpose of obtaining an arrestee’s DNA was for crime solving, and it justified the intrusion into the arrestee’s privacy largely on the grounds that the Government would use the DNA collected to identify the arrestees. Since DNA was merely a better, more advanced form of fingerprinting, the Court argued, the use of the DNA collected from arrestees significantly furthered the Government’s interest in identification. The Court in Riley, however, recognized that a search of an arrestee’s cell phone could be for nothing more than general criminal investigation.

The Court’s holding in King is impossible to square with its holding in Riley. If a search warrant is required for police to search an arrestee’s cell phone, it follows that a search warrant should be required to search a person’s DNA. Given the significantly broader protection granted to arrestees in the later Riley decision, King has been doctrinally eroded.

In light of this doctrinal erosion and the unlikelihood that the Court will overturn King in the near future, lower courts should interpret King narrowly. State DNA statutes should be upheld only if they match the specific holding in King. DNA searches should be permissible only if the person was arrested for a violent felony, and the arrest was supported by a judicial determination of probable cause. Furthermore, if the investigation into the arrestee ceases or the charges are dropped, the DNA sample should be automatically destroyed and the records automatically expunged from the state and Federal DNA databases.

Keywords: DNA, Cell Phones, Fourth Amendment, RIley v. California, Maryland v. King

Suggested Citation

Silk, Jennie, Calling Out Maryland v. King: DNA, Cell Phones, and the Fourth Amendment (January 21, 2015). Available at SSRN: or

Jennie Silk (Contact Author)

University of Mississippi - School of Law ( email )

Lamar Law Center
P.O. Box 1848
University, MS 38677
United States

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