Almost nine years after Volkswagen admitted that it had rigged millions of cars to cheat on emissions tests, the company’s former chief executive went on trial Tuesday on charges stemming from the fraud, a vast corporate conspiracy that changed the auto industry.
Martin Winterkorn, 77, who led Volkswagen from 2007 until he resigned under pressure in September 2015, appeared at a court in Braunschweig, Germany, after a judge rejected his pleas to postpone the trial because he said he was in poor health. The trial will be a test of whether German authorities can hold top executives accountable for wrongdoing that cost Volkswagen tens of billions of dollars and contributed to poor air quality in Europe and the United States.
Mr. Winterkorn, who was once Germany’s highest-paid executive, faces criminal charges including fraud, market manipulation and making false statements. Prosecutors accused him of failing to notify authorities and owners of Volkswagen cars when, in 2014, he became aware of software designed to illegally cloak emissions that exceeded limits imposed by European and U.S. regulators.
With Mr. Winterkorn’s knowledge, prosecutors said, Volkswagen continued to sell such vehicles until the cheating was exposed by California regulators and the Environmental Protection Agency in 2015. Over a decade, Volkswagen and its Audi, Skoda and Seat units sold nine million cars with the illicit software.
Prosecutors have also accused Mr. Winterkorn of authorizing a recall of the affected vehicles in 2014 with the purpose of preventing regulators from learning about the forbidden software. And he is accused of lying under oath to a German parliamentary committee investigating the cheating.
The market manipulation charge arises from allegations that Mr. Winterkorn failed to notify Volkswagen shareholders of the financial risk posed by the software as required by securities law.
The trial started on Tuesday, with prosecutors reading all three indictments against Mr. Winterkorn, who arrived early wearing a dark blue suit. He looked tired as the charges were read, but his lead attorney, Felix Dörr, said Mr. Winterkorn was in good health.
The case illustrates how difficult and time-consuming it can be for prosecutors to hold high-ranking corporate managers accountable for illegal activity that takes place on their watch. Mr. Winterkorn, who was known for his authoritarian management style and short fuse, has insisted that he had no knowledge of the cheating, blaming underlings for the wrongdoing.
The trial comes at an inopportune time for Volkswagen, which faces profitability problems amid increasing pressure from Asian competitors. On Monday, the carmaker warned that it would consider closing factories in Germany for the first time in its 87-year history, ending a decades-old guarantee of job security for workers.
The wheels of justice moved exceptionally slow in Mr. Winterkorn’s case. The trial was postponed repeatedly while he received treatment for knee and hip problems. But the court in Braunschweig, a city near Volkswagen’s headquarters in Wolfsburg, rejected his most recent pleas to delay the proceedings.
The charges carry a maximum of 10 years in prison, although it is unusual for German judges to impose long prison sentences for white-collar crimes. Rupert Stadler, the former chief executive of Volkswagen’s Audi unit, received a suspended sentence last year after he pleaded guilty to charges related to the scandal.
The illegal software that Volkswagen used recognized when a diesel vehicle’s emissions system was being tested and dialed up pollution controls to comply with regulations.
At other times, the cars spewed excessive quantities of toxic nitrogen oxides, which cause asthma and other respiratory problems. The engines’ emissions systems were not capable of consistently operating within legal limits.
The scandal has had long-lasting effects on the auto industry. Volkswagen and other carmakers had, for years, marketed cars that ran on diesel as cleaner alternatives to gasoline cars. They argued that diesel cars had better fuel economy, and therefore emitted less greenhouse gases.
Few people listened to environmental activists who pointed out that pollution levels in European cities were much higher than they should have been if the technology was as clean as advertised.
Volkswagen’s wrongdoing, which was initially uncovered by graduate students at West Virginia University working with a $70,000 grant, exposed the degree to which the auto industry had obscured the hazards of diesel.
Other automakers including Fiat Chrysler, now part of Stellantis, and Mercedes-Benz paid fines to settle accusations they had also illegally concealed emissions, though none was accused of doing so on the same scale as Volkswagen, the second-largest carmaker in the world after Toyota.
The scandal prompted European authorities to tighten air quality standards and encourage sales of electric vehicles, which have surpassed diesels in popularity. Diesels once accounted for more than 50 percent of new cars in Europe, but recently accounted for 13 percent.
In the United States, Volkswagen agreed to pay $15 billion to settle civil and criminal claims stemming from the scandal. That included fines, compensation to owners of diesel vehicles and a fund that local governments could tap to buy electric school buses or pay for other projects to reduce air pollution. As part of the settlement, Volkswagen funded the creation of Electrify America, which operates one of the largest electric car charging networks in the country today.
Testimony in German criminal trials does not always take place on consecutive days, and the proceedings can last years. Four lower-ranking Volkswagen executives have been jointly on trial in Braunschweig since 2021. That trial is expected to last until January.
Outside the courthouse on Tuesday, Matti Holtz, a Volkswagen factory worker and a father of two, stood with others while carrying a protest poster. Mr. Holtz, who owns a Volkswagen, said he wished punishment for Mr. Winterkorn, not only for the “fraud of the customers,” but also because of the “intentional poisoning of people and nature.”
The court has scheduled about 90 days of testimony in Mr. Winterkorn’s case, which is expected to last until September 2025.