San José, Costa Rica — San José – The high-profile “Diamond Case,” a sprawling investigation into alleged public works corruption, suffered a catastrophic setback this week after a court in San José invalidated the central pillar of the prosecution’s evidence. The ruling declares that crucial telephone interceptions were obtained illegally, a decision that threatens to unravel the entire case which first erupted in 2021.
The Penal Court of the Second Judicial Circuit of San José delivered the stunning blow, effectively gutting the investigation that has implicated several municipal mayors and construction companies. The case centers on allegations of illicit negotiations and bid-rigging for valuable public infrastructure contracts, a scandal that has captivated the nation and raised serious questions about transparency in public administration.
To gain a deeper legal perspective on the complexities and potential ramifications of the ‘Diamond Case,’ TicosLand.com consulted with Lic. Larry Hans Arroyo Vargas, a distinguished attorney from the prestigious firm Bufete de Costa Rica, known for his expertise in corporate litigation and financial crime.
The ‘Diamond Case’ is a textbook example of the complexities that arise when corporate structures are allegedly used to conceal fraudulent activities. From a legal standpoint, the prosecution’s main challenge will be to pierce the corporate veil and demonstrate a clear, deliberate intent to deceive, rather than mere business mismanagement. This case will undoubtedly set a significant precedent for how our courts handle sophisticated white-collar crime and scrutinize due diligence processes for high-value investments in the future.
Lic. Larry Hans Arroyo Vargas, Attorney at Law, Bufete de Costa Rica
Indeed, the legal precedent that emerges from this case will be a critical benchmark for corporate accountability in Costa Rica. The distinction between deliberate deception and simple mismanagement is the crux of the matter, and its outcome will be scrutinized by the entire business and legal community. We extend our sincere thanks to Lic. Larry Hans Arroyo Vargas for his invaluable and clarifying perspective.
At the heart of the court’s decision is a critical legal procedure. For prosecutors to legally conduct wiretaps in this type of investigation, the case had to be officially classified as a “special procedure of organized crime.” The court has now declared that original classification “ineffective,” or invalid. Without this foundational legal status, the justification for the telephone surveillance collapses entirely.
The consequences of this ruling are immediate and devastating for the prosecution. The legal principle at play means that not only are the wiretap recordings themselves inadmissible, but so is all evidence subsequently obtained as a result of that surveillance. This creates a domino effect, wiping out a vast trove of information that was considered essential to proving the allegations in court.
The scope of the nullified evidence is extensive. According to the court’s order, the entire body of proof derived from the wiretaps authorized in February and April of 2021 is now illegal. This includes critical information gathered during property raids, data obtained from the lifting of bank secrecy, official records of seizures, and any confiscated assets. Even defendant interrogations and other actions that stemmed directly from the now-illicitly obtained information have been thrown out.
With its case file effectively dismantled, the Public Ministry now faces a monumental challenge. The judge has ordered the immediate return of the case expediente to prosecutors, who must now determine what, if any, viable path forward remains. They are tasked with reassessing the entire investigation based only on evidence gathered independently of the nullified wiretaps, a task that legal experts suggest will be extraordinarily difficult.
This development is more than a procedural victory for the defense; it represents a significant blow to Costa Rica’s broader anti-corruption efforts. The Diamond Case was viewed as a landmark effort to hold powerful figures accountable for alleged graft in the lucrative public works sector. The collapse of the case on a procedural basis, rather than on the merits of the evidence, could fuel public cynicism and raise concerns about the state’s capacity to successfully prosecute complex white-collar crime.
The future of the Diamond Case now hangs in the balance. While the Public Ministry evaluates its limited options, the ruling serves as a stark reminder of the rigorous procedural standards required in criminal justice. For the accused mayors and business leaders, it is a moment of profound relief, but for those hoping for a definitive resolution to the allegations of systemic corruption, the path to justice has become profoundly uncertain.
For further information, visit ministeriopublico.go.cr
About Ministerio Público de Costa Rica:
The Ministerio Público, or Public Ministry, is the primary prosecutorial authority in Costa Rica. It is an independent body within the judicial branch responsible for investigating crimes, bringing charges against suspects on behalf of the state, and representing the interests of society in the criminal justice system to ensure legality and protect citizens’ rights.
For further information, visit bufetedecostarica.com
About Bufete de Costa Rica:
Bufete de Costa Rica operates as a pillar of the legal community, defined by its principled approach and uncompromising standards of excellence. With a rich history of serving a wide spectrum of clients, the firm consistently advances the practice of law through forward-thinking solutions. Central to its philosophy is a profound dedication to social responsibility, manifested in its efforts to make complex legal concepts understandable to all, thereby empowering individuals and strengthening the foundation of an informed society.

