The Duquenois-Levine field test cannot distinguish marijuana from industrial hemp. For any criminal offenses, the evidence should be submitted to the laboratory. DFS no longer provides Duquenois-Levine field tests to law enforcement agencies. Although Virginia Code §19.2-188.1(B) permits a law enforcement officer to testify as to the results of marijuana field tests that have been approved by DFS in any trial for a violation of § 18.2-250.1, there are currently no marijuana field tests that have been approved by DFS for this purpose.
Duquenois-Levine field tests and others have been approved for detection of Marijuana when used under § 19.2-188.1(A). Virginia Code §19.2-188.1(A) permits a law enforcement officer to testify as to the results of field tests in any preliminary hearing for a violation of Chapter 11 (§ 4.1-1100 et seq.) of Title 4.1, Article 1 (§ 18.2-247 et seq.) of Chapter 7 of Title 18.2, or subdivision 6 of § 53.1-203.
The field tests for detection of drugs for use in preliminary hearing under § 19.2-188.1(A) that have been evaluated and approved by the Department of Forensic Science are accessible at the in the links below.