As well as the expert report which should clearly identify the result of your clients drugs testing, it is important to understand the actual drugs result. There are a number of terms listed on the reports.
- not detected – this means the laboratory was not able to detect any drugs in the hair sample at the levels they are able to be detected.
- limit of detection (lod) – the lowest level the laboratory can detect to. Above the limit of detection the laboratory knows that drugs are in the hair but are unable to advise exactly how much, i.e. Cocaine use could be 0.05ng/mg to 0.15ng/mg but it is not possible to pin point.
- limit of quantification (loq) – the level above which that the lab can accurately identify the drug within the hair for example where the lab can report cocaine use of 0.24ng/mg v 0.25ng/mg
- cut-off level – this is the level that once a result is above, it is considered positive for drug use. There is no agreed cut-off level in care proceedings although many firms use the SoHT cut-off’s for workplace drug testing. In forensic cases or when trying to establish one of doses of drugs, the cut-off level will be above the LoQ.
To Consider – There is no agreed positive cut-off level for drugs of abuse in UK care and family proceedings. Whilst many labs report results in line with workplace testing levels, set by the SoHT, this is not always the correct cut-off level to use. What this means in practice is that each testing company can use whatever measure they deem fit and as legal advisors, you may not even be aware of the level of cut-off that is used in the testing, or whether it is relevant to the client or not. Due to this lack of consensus, a wide variety of results can be generated. A client can either test positive for a line or two of cocaine per month, or equally well the same test can be classed as negative.
We have the ability to determine with precision how much and when a drug has been ingested, and can build an accurate picture of the individual clint’s usage or abstinence, which can hugely affect a court decision. We at DNA Legal, consider this to be a major issue in the justice system, which is not adequately addressed in court, and can lead to a miscarriage of justice for clients.