Forensic science is sometimes not used very well. Sometimes labs and police don't do forensic measurement properly. They forget that what they are doing is going to be used for a forensic purpose.
The Motherisk Inquiry Report in Ontario studied the causes of miscarriages of justice that occurred in Ontario a few years ago. A lab in Toronto was using the forensic tool "hair analysis" to determine if mothers were drug abusers. Children were taken away from their parents in child protection Courts. Parents were prosecuted criminally. Forensic science was being abused. The measurements taken and reported to the Courts were unreliable.
Justice Lang stated the following at page 78 of her inquiry report:
"Forensic science involves the application of scientific knowledge and methodology to legal problems. However, a forensic test is not necessarily one that will be used in the justice system; a test will be forensic if it is carried out or used for a legal (or medico-legal) purpose. In the hair-testing context, medico-legal purposes include detecting use of or exposure to drugs for the purposes of child protection or family law cases (e.g., as evidence of drug use by a parent or child), as well as in criminal proceedings (e.g., as evidence of whether a complainant, accused, deceased, or other witness was drugged). Other forensic (or medico-legal) purposes that may not necessarily involve a courtroom at first instance, but may nonetheless have legal implications, include workplace drug testing or sports testing for banned substances."
Justice Lang noted that there are differences among tests for research purposes, clinical purposes, and forensic purposes. It is a mistake to confuse those purposes. Tests originally run for research purposes or clinical purposes should not be used for forensic purposes unless special care is taken. Tests originally run for clinical purposes might later be used for purposes that affect Court proceedings. That can happen in child protection proceedings.
I suggest that could also happen in Youth Court proceedings. Let's suppose that a young person is involved in a car accident and goes to the hospital. The doctors and nurses draw blood for clinical purposes. The police get a search warrant and seize the lab results from the hospital. The lab results show the presence of or a quantitative result of drugs or alcohol.
Justice Lang states on page 78: "there can be a blurring of the lines between the clinical and the forensic worlds. In some cases, it may be appropriate to use a clinical test for forensic purposes with that caveat; in others, it may be more appropriate to rerun the test in a forensic setting before relying on it for forensic purposes."
However, there are big differences in the standards used by forensic labs, than those used by other labs. Justice Lang notes at page 78:
"37. It is important to distinguish among research, clinical, and forensic purposes because different standards apply, depending on the manner in which the hair test is intended to be used. Forensic laboratories have the most stringent requirements, including strict chain-of-custody procedures and documentation standards to reduce the risk of contamination of samples and to ensure the traceability and reliability of the results obtained."
So in Youth Court, if analytical results are going to be used as evidence against the young person, we need to be concerned about:
strict chain-of-custody procedures,
traceability of measurement results, and
reliability of measurement results
One of the many problems discovered by the Motherisk Inquiry was the failure to distinguish between qualitative analysis and quantitative analysis. See the Motherisk glossary at page xix:
A result that provides an indication of drug presence as a positive (yes) or negative (no), rather than providing actual quantitative results."
A result that is reported containing the actual concentration of the drug in a sample, indicating a degree of precision and accuracy."
Police and others sometimes use screening tests to identify the presence of a drug. Screening tests produce a qualitative result. Sometimes they produce a semi-quantitave result (e.g. an "approved screening device"). However, if the alleged result being put before the Court is "quantitative" then a whole lot of special scientific rules have to apply, prior to admission into evidence, because the evidence is of an actual concentration with a degree of precision and accuracy.
Courts and lawyers need to pay careful attention to the lessons of the Motherisk Inquiry concerning the misuse of qualitative assessment, specifically screening tests being used as quantitative analysis. Courts and lawyers also need to pay close attention to the misuse of quantitative analysis when labs and police are not properly accredited or don't follow international standards. See page 4 of the Motherisk Inquiry Report:
"To be used in child protection or criminal proceedings, forensic tests must be carried out in accordance with forensic standards. International forensic standards are articulated in several sources ...
the standards that are required to be met for the accreditation of forensic laboratories (including the requirements under ISO 17025:2005, General requirements for the competence of testing and calibration laboratories);
best practices that are commonly accepted and recognized by forensic toxicology laboratories around the world ..."
If there is to be forensic science evidence of a quantitative analysis measurement in Youth Court, then the lawyers and the Court need to be concerned with:
accreditation of the entity performing the measurement,
compliance with good laboratory practice.
Ask your Youth Court lawyer if the evidence that the Crown intends to produce against you contains a quantitative analysis. If it does the you and your lawyer will need to research whether the police or lab are accredited for that type of analysis and whether they have complied with good laboratory practice. You and the Court will need to pay close attention to the accuracy and precision of the measurement result.