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Controlled Substances FAQ

Frequently Asked Questions for Controlled Substances

  • Can I still submit a suspected marijuana pipe or scale for analysis?

  • No, unless it is a juvenile case or drugs other than marijuana are suspected.  As indicated in the Policy Notice dated June 23, 2020, DFS is not able to quantify the THC concentration in residues and is unable to distinguish whether any cannabinoids identified in residues are hemp-derived or marijuana-derived.  Accordingly, residues should not be submitted for analysis.

  • Will DFS continue to accept cases for felony possession of marijuana by prisoners?

  • Yes, DFS will continue to analyze, without a court order, plant material in cases involving felony possession of marijuana by prisoners.  Please note “felony possession” on the RFLE when submitting this evidence.

  • Will DFS continue to accept cases for possession with intent to distribute marijuana?

  • Yes.  The revised marijuana submission policy is only applicable to cases where the charge is possession of marijuana. There is a rebuttable presumption under Virginia Code § 18.2-248.1 that less than 1 ounce is for personal use.

  • Will DFS continue to accept marijuana evidence for juvenile cases?

  • Yes.  The revised marijuana submission policy is only applicable to possession of marijuana cases for adults.

  • Can the Department of Forensic Science analyze marijuana edibles?

  • While the Department can identify specific cannabinoids, DFS cannot distinguish between marijuana-derived and hemp-derived edibles.

  • Does DFS test agricultural plants grown as hemp if they are suspected to be above the 0.3% THC limit?

  • DFS does not perform testing for compliance with tetrahydrocannabinol (THC) limits in support of hemp regulatory programs.

  • What types of suspected marijuana evidence should be submitted to the lab for further testing?

  • Evidence to consider submitting to the lab includes what has tested positive with the Duquenois-Levine test kit in conjunction with a blue color formation (indicative of Marijuana) or an inconclusive result with the Cannabis Typification or 4-AP field test (excluding simple possession of marijuana cases that may only be submitted with a court order).  Evidence that has shown a pink color formation (indicative of industrial hemp) for the Cannabis Typification or 4-AP field test should only be submitted to the lab for further testing if needed for court purposes.  For Virginia Code § 18.2-250.1 offenses on or after July 1, 2020, the evidence will need to be accompanied with a court order at the time of submissions.

Controlled Substances – Marijuana Field Test Kits

  • What if the results of the marijuana field test kit are inconclusive?

  • If the Duquenois-Levine test is positive and the results of the Cannabis Typification or 4-AP field test are inconclusive, meaning there is no color change or it turned purple, repeat with another test kit on a separate sample.  A color change to purple may indicate the sample size is too large. Consider submitting evidence when results remain inconclusive (excluding simple possession of marijuana cases that may only be submitted with a court order). For § 18.2-250.1 offenses on or after July 1, 2020, the evidence will need to be accompanied with a court order at the time of submission.  Note on the Request for Laboratory Examination (RFLE) that the field test results were inconclusive.

  • Can the Duquenois-Levine field test tell the difference between hemp and marijuana?

  • No, the Duquenois-Levine field test cannot distinguish marijuana from industrial hemp.

  • Can you walk me through how and when to use the Cannabis Typification or 4-AP field test?

  • Please see the Department’s website for both written instructions and an instructional video on how to use this test kit.  The direct link for this information can be found at: https://dfs.virginia.gov/field-test-kits/4-ap-cannabis-typification-field-tests/ These tests should be used on plant material that has tested positive for Cannabis using the Duquenois-Levine test kit, and further information is needed as to whether it is more likely to be marijuana or industrial hemp.

  • How should the results of the Cannabis Typification or 4-AP field test be interpreted?

  • The results from the Cannabis Typification or 4-AP field test can be interpreted in one of four ways:
    • Blue color formation: Indicative of Marijuana (delta-9-THC concentration is greater than that of Cannabidiol).  The sample should be submitted to DFS for further analysis if criminal charges are to be pursued (excluding simple possession of marijuana cases that may only be submitted with a court order).
    • Pink color formation: Indicative of Hemp (Cannabidiol concentration is greater than that of delta-9-THC).  This sample should not be submitted to the lab for further testing unless the adjudication of the case hinges upon THC concentration determination down to 0.3% as defined in the Code of Virginia.  This method is currently being developed and validated by the Department.
    • Purple or dark blue color formation: Inconclusive result.  The test was likely conducted using too much plant material, and should be performed again using a fresh test kit and an appropriate amount of sample.  The appropriate amount of sample should be about the size of a grain of rice.
    • No color change: Inconclusive result.  Repeat the test again using a fresh test kit with an appropriate amount of sample.  The appropriate amount of sample should be about the size of a grain of rice.
    For more information, please see the 4-AP informational page: https://dfs.virginia.gov/field-test-kits/4-ap-cannabis-typification-field-tests/

  • Do I use a Cannabis Typification or 4-AP field test for all plant material?

  • No.  Only use a Cannabis Typification or 4-AP field test if the sample has initially tested positive with a Duquenois-Levine test kit.

  • Is the Cannabis Typification or 4-AP field test only used to determine if the material is hemp?

  • The Cannabis Typification or 4-AP field test is able to give an indication of whether your sample is more likely to be industrial hemp or Marijuana.

  • Do I use the Cannabis Typification or 4-AP field test if the Duquenois-Levine test kit was negative?

  • No.  The Duquenois-Levine test kit gives a presumptive positive for Cannabis plant material.  If this test is negative, there is no need to proceed further with a Cannabis Typification or 4-AP field test.

  • Do the Cannabis Typification or 4-AP field test kits need to be stored in any particular way before use?

  • The test kits should be kept out of direct sunlight for prolonged periods of time.  Otherwise they should maintain their integrity under normal working conditions.