The Andrew Malkinson case highlights egregious failings in the criminal justice system, but also the unique power of forensic scientific evidence to bring about redress. In 2007, three years after Malkinson’s conviction and after scientific advances, a new DNA profile was identified from the victim’s clothing, which had been securely archived after the original trial. This was crucial to Malkinson’s eventual exoneration and could yet help bring the right person to justice. The secure storage of scientific evidence is a cornerstone of the criminal justice system, enabling the prosecution of dangerous criminals, triggering breakthroughs in cold cases, and ensuring the ability of innocent people to appeal against wrongful convictions. However, experts are concerned at what appears to be an increasing number of instances in which crucial forensic evidence is being lost, destroyed or damaged. The past decade has seen an overhaul of forensic science provision in the UK after the closure of the Forensic Science Service in 2012. In the transition, criticism has largely focused on private providers, which have been behind the drug-driving test scandal at Randox, the multimillion-pound bailout of Key Forensics and the use of unaccredited labs. Many hope that commercial provision is now on a safer footing after the introduction this year of statutory powers for the government’s forensic science regulator, including the ability to shut down labs that do not meet quality standards. However, as police budgets have tightened, many forces are opting to carry out the more routine elements of forensic science work in house; a 2019 House of Lords report suggested that 80% of the work is carried out by police labs. The same report found that police spending on forensic science in England and Wales fell by more than half, from £120m in 2008 to an estimated £50m-£55m in 2018. And crucially, the storage and archiving of forensic evidence before and after trial does not come under the forensic science regulator’s remit. Since 2012, responsibility for securing, retaining and archiving exhibits, samples, case notes and digital materials has fallen to the 43 individual police forces in England and Wales. In recent research, Prof Carole McCartney, a criminologist at the University of Leicester, described the police retention of evidence as “an opaque, unaudited landscape”, but the glimpses available paint worrying inconsistencies. In responses given at the time of that research, some forces appeared to apply policies that would mean forensic science materials are destroyed far sooner than national guidance indicates, with others keeping material for 100 years, creating an unnecessary storage burden. Freedom of information requests show that more than 7,000 cases were dropped before trial last year due to evidence being lost or otherwise becoming unavailable, including 16 homicides and 123 sex offences. And interviews with serving and retired officers found that, while some reported that forensic science storage was functioning well, most had experienced instances of being unable to locate seized evidence or of problems with the integrity and security of storage. Several spoke of inadequate storage facilities and severe capacity problems affecting the storage of evidence for serious crimes. Last week the government announced its ambition to improve police investigations. The home secretary said that police forces would be expected to consider “all available evidence” to drive down crime rates for thefts and burglaries. However, for scientific evidence to be useful, it needs to be securely stored and available for as long as is required by the criminal justice system.