The Argentina submarine implosion trial opened on Tuesday in Santa Cruz province, eight years after the sinking of the ARA San Juan killed 44 sailors in the country’s deadliest naval disaster in decades.
The proceedings are taking place in Rio Gallegos, the provincial capital of Santa Cruz, near where the submarine’s wreckage lies more than 900 metres below the South Atlantic seabed, approximately 400 kilometres off Argentina’s southern coast. The vessel disappeared on 15 November 2017 while returning from Ushuaia to its home port at the Mar del Plata naval base.
The ARA San Juan, a diesel-electric submarine, reported that seawater had entered its ventilation system, causing a battery short circuit and fire shortly before contact was lost. More than a dozen countries joined the international search operation. The wreckage was located a year later, severely crushed by pressure at extreme depth.
Federal prosecutors have charged four former naval officers with dereliction of duty and aggravated negligent destruction. The defendants are Luis Lopez Mazzeo, former chief of Training Command; Claudio Villamide, former Submarine Force commander; Hector Alonso, former chief of staff of the Submarine Command; and Hugo Correa, former head of operations. If convicted, they face prison sentences of between one and five years.
In 2021, a military court dismissed Claudio Villamide for negligence and sentenced other officers to short custodial terms of up to 45 days for concealing information related to the disaster. Civil proceedings now aim to determine broader criminal accountability within Argentina’s naval command structure.
Valeria Carreras, a lawyer representing 34 of the victims’ families, described the sinking as an avoidable tragedy and accused the Navy of maintaining a culture of silence. She said financial constraints have prevented most relatives from attending the hearings in Rio Gallegos.
Luis Tagliapietra, whose 27-year-old son Alejandro died aboard the submarine, had requested that the trial be held in Mar del Plata, where many crew members were based. The court rejected the request. Tagliapietra criticised the decision to hold proceedings far from Buenos Aires, arguing it limits public visibility of the case.
The disaster also triggered a political scandal after it emerged that former president Mauricio Macri authorised illegal surveillance of victims’ relatives. Macri was prosecuted in connection with the case, which was later closed by Argentina’s Supreme Court last year.
Investigators have advanced the hypothesis that a valve failure allowed seawater to enter the battery compartment, triggering a fire followed by an internal explosion. However, confirming the precise sequence of events would require salvaging the wreckage from the ocean floor, a complex and costly operation estimated to run into tens of millions of dollars.
Legal experts note that establishing criminal liability may prove difficult without definitive technical evidence from the submarine itself. Hearings are scheduled over four consecutive days, followed by a one-week recess before further sessions.
The Argentina submarine implosion trial marks a significant test for judicial accountability in military governance, defence oversight and state transparency, as families continue to seek clarity over the circumstances that led to the loss of 44 service members.
