In Virginia, the law allows certain felony arrestees to have their DNA samples taken upon arrest. I have no doubt that they have his DNA directly from him:
Virginia's Arrestee's Experience
On January 1, 2003, the state of
Virginia was the first state to collect DNA from people who were arrested for certain violent and sex crimes. This law was passed under the condition that if the person arrested was later found to be innocent or if the charges were dropped, the arrestees' DNA profile would automatically be destroyed and removed from Virginia DNA Database. The arrestee law has proven to be beneficial in catching repeat offenders. Between January 1, 2003 and December 31, 2009, a total of 559 hits to the Arrestee Database have been obtained. Eighty-nine of the hits were associated with sexual assault cases.
http://www.dnaforensics.com/Arrestees.aspx
Virginia Law:
§
19.2-310.2:1. Saliva or tissue sample required for DNA analysis after arrest for a violent felony.
Every person arrested for the commission or attempted commission of a violent felony as defined in §
19.2-297.1 or a violation or attempt to commit a violation of §
18.2-31,
18.2-89,
18.2-90,
18.2-91, or
18.2-92, shall have a sample of his saliva or tissue taken for DNA (deoxyribonucleic acid) analysis to determine identification characteristics specific to the person. After a determination by a magistrate or a grand jury that probable cause exists for the arrest, a sample shall be taken prior to the person's release from custody. The analysis shall be performed by the Department of Forensic Science or other entity designated by the Department. The identification characteristics of the profile resulting from the DNA analysis shall be stored and maintained by the Department in a DNA data bank and shall be made available as provided in §
19.2-310.5.
http://www.ncstl.org/resources/DNACollectionUponArrest
