Children are at risk of being wrongly removed from their parents’ care by the family courts because drug tests are being misinterpreted, experts have warned.
Life-changing decisions about whether a child should be placed in the care of a local authority can sometimes hinge on the outcome of hair-strand tests, designed to show whether a parent has consumed drugs or excessive alcohol.
But the process used to interpret the results can be misleading and carries a risk of racial bias, according to lawyers and campaigners.
Paul Hunter, an expert in the field of drug testing, told The Bureau of Investigative Journalism that “non-drug users are losing their children” due to the misreporting of hair-strand test results.
Hair-strand testing has been in use since the 1990s and is commonplace in family courts. When a person uses a drug, such as cocaine, its presence within the bloodstream means traces of it are incorporated into the hair as it grows. But crucially, the levels of drug present in the hair do not equate to drug consumption when looked at in isolation.
Data collected by hundreds of researchers over the past 30 years shows that numerous factors, including race, hair colour, pregnancy and exposure to UV rays, can affect the amount of a drug absorbed in a sample of hair, as can the use of certain hair products. Significant levels of a drug can be found in someone’s hair because they share a living space with drug users. Meanwhile, low levels of a drug – or none at all – can be found in hair taken from a regular user – for example, if it has been dyed or treated.
The issue of test results being misreported is the subject of an open letter sent on Tuesday to the family division of the high court. The letter, signed by lawyers, academics and campaigners, calls for urgent reform to how results are presented in court as evidence.
Sir Andrew McFarlane, president of the family division of England and Wales, said: “Concerns about the accuracy and interpretation of drug tests are taken very seriously.” He has referred the issue to the Family Justice Council “for urgent consideration”.
Hair strand testing can be used in public law cases – where the local authority may have concerns about the impact of substance misuse on a child – and private disputes where one parent may raise a complaint about the other’s drug or alcohol use.
Hunter, technical director at Forensic Testing Service Ltd, is brought in as an expert witness to advise the courts in complex cases or when there are conflicting results from different labs.
He said the biggest problem is the use of “cut-off levels”, the threshold above which a person is considered to be a drug user. The cut-off levels were developed by the Society of Hair Testing almost 30 years ago, long before research established what is now known about the impact of influencing factors on drug absorption, such as hair colour, race and environmental factors.
Nevertheless, many drug companies continue to use the binary system of cut-off levels to report test results. This is despite discrepancies such as the fact that hair with darker pigmentation will absorb drugs more readily. This leads to a person who has black hair having dramatically higher levels compared with those who have light brown or blond hair, even if they have identical drug use.
Furthermore, within the subsection of black hair there are huge variations based on race, meaning people of African-Caribbean, African or Asian descent are more likely to lose custody of their child.
“The danger is that ‘positive’ and ‘negative’ results are being treated at face value without room for wider interpretation,” said Hunter. “Social workers and parenting assessors advising the courts will often equate the level of drug detected in the hair as evidence of drug consumption, which is dangerous and wrong.”
The open letter sent to the family division states: “There is a compelling body of evidence that shows the processes used to interpret the results are vastly oversimplified and misleading.” It calls for an end to “discriminatory” cut-off levels and warns of the “risk of systematic racial bias”.
It has been long-established that the use of hair strand testing in isolation should not be relied on. In a 2017 judgment, Mr Justice Hayden wrote that hair strand testing “should never be regarded as determinative or conclusive”.
One group of particular concern is pregnant women and new mothers, because of the significant growth in the rate of infant care proceedings. Child protection proceedings for newborn babies have risen from more than 1,000 in 2007/2008 to nearly 2,500 in 2016/2017.
“If you are a first-time mother, you have a lot to prove in a short time frame about your capacity to parent and your commitment to addressing some of the issues that might have led to the concerns including substance use,” says Kirsty Kitchen, head of policy at Birth Companions.
The charity, which supports women who experience disadvantage in the justice system, organised the open letter and formed the campaign, Taking A Strand, along with barristers from 4PB and MSB Solicitors.
Kitchen said: “A positive hair strand test can be the sole or most significant factor regardless of everything else. If that is not contextualised, or if it is unreliable, then we have a major issue.”
Family law barrister Lucy Logan Green has become concerned about the growing number of her clients who have questioned the accuracy of hair strand test results.
In one case a mother’s alleged ongoing cannabis use was one factor the court was considering when faced with whether her child in local authority care should be returned to her or placed for adoption.
Logan Green’s client was adamant she was abstinent from all cannabis use but the most recent hair strand tests returned positive results for low-level use. The court ordered that the child should be placed for adoption.
The barrister explained: “I wrote to the testing company to ask whether the low levels of cannabis detection could be caused by environmental contamination and they responded saying it could be. But that information hadn’t been provided within the company’s analysis.”
Logan Green is among the signatories to the open letter, copied to the Family Justice Board, the government body responsible for improving the family justice system in England and Wales.
It cites a court of appeal judgment published in May in which Mr Justice Cobb concluded another judge had been wrong to attach “such presumptive weight” to a set of hair strand test results that led them to order the removal of three children from their family. Cobb overturned the decision.
The case highlights that test results, when presented without context, can be highly misleading. The advocates involved were criticised for providing only a brief summary of the test results to the judge – and omitting the comprehensive interpretation and opinions provided by the expert in the body of the report.
The open letter argues hair-strand testing should be treated by the courts as expert opinion evidence and warns: “Without urgent and comprehensive review of the way this evidence is presented and interpreted in court proceedings, there is significant risk that many more children will be wrongly removed from their families: a most devastating form of injustice.”
A spokesperson for HM Courts and Tribunals Service said: “While ultimately decisions are made by the independent judiciary, it is extremely unlikely a single hair strand test would result in a parent losing custody.”
However, Logan Green said that if hair strand testing was ordered at the outset, loss of custody becomes a more likely outcome. “At the start, if you are considering the removal of a child there may not be much other evidence to go on. A positive drug test for an illicit substance can and absolutely does lead to removals.”
