Volkswagen is accused of using software in four-cylinder Volkswagen and Audi diesel cars from model years 2009 to 2015.
"I probably wouldn't do much," Buffett said when asked what he would do if he ran the Fed.
The ruling by US Judge Steven Rhodes, who cited the city's dismal finances and $18 billion owed to a multitude of creditors in support of his decision, marks a watershed in the history of Detroit.
Retirees and labour officials acknowledged that the city's finances were in a shambles and they would have to share in the sacrifice to help Detroit recover.