In June 2013, a Chilean judge ordered that an investigation be launched, following suggestions that Neruda had been killed by the Pinochet regime for his pro-Allende stance and political views. Neruda's driver, Manuel Araya, stated that doctors had administered poison as the poet was preparing to go into exile. In December 2011, Chile's Communist Party asked Chilean Judge Mario Carroza to order the exhumation of the remains of the poet. Carroza had been conducting probes into hundreds of deaths allegedly connected to abuses of Pinochet's regime from 1973 to 1990. Carroza's inquiry during 2011–12 uncovered enough evidence to order the exhumation in April 2013. Eduardo Contreras, a Chilean lawyer who was leading the push for a full investigation, commented: "We have world-class labs from India, Switzerland, Germany, the US, Sweden, they have all offered to do the lab work for free." The Pablo Neruda Foundation fought the exhumation under the grounds that the Araya's claims were unbelievable.
In June 2013 a court order was issued to find the man who allegedly poisoned Neruda. Police were investigating Michael Townley, who was facing trial for the killings of General Carlos Prats (Buenos Aires, 1974), and ex Chancellor Orlando Letelier (Washington, 1976). The Chilean government suggested that the 2015 test showed it was “highly probable that a third party” was responsible for his death.
Test results were released on 8 November 2013 of the seven-month investigation by a 15-member forensic team. Patricio Bustos, the head of Chile's medical legal service, stated "No relevant chemical substances have been found that could be linked to Mr. Neruda's death" at the time. However, Carroza said that he was waiting for the results of the last scientific tests conducted in May (2015), which found that Neruda was infected with the Staphylococcus aureus bacterium, which can be highly toxic and result in death if modified.