In total, O'Quinn is estimated to have won $1.5 billion for the firm of O'Quinn, Laminack & Pirtle of Houston, Texas. Now running his own firm, pending are cases against stock brokers and hedge funds for shorting the shares of weak companies, and against Ford for rollover accidents caused by the Ford Explorer.
O'Quinn received a public reprimand in 1989 from the State Bar after a lengthy investigation into allegations that his firm had wrongfully solicited cases. Family members of victims have charged that they were approached by O'Quinn's lawyers, and their agents after a July 2, 1994 USAir jet crash in North Carolina. In 2007, an arbitration panel ruled that O'Quinn had improperly withheld $18.9 million in settlement money from breast implant clients; the federal court overseeing the breast implant litigation issued an order to show cause why the O'Quinn Law Firm should not be held in contempt of court. On July 19, 2007, the same arbitration panel ordered O'Quinn to pay $35.7 million plus attorneys' fees and interest. The panel upped the award to $41.4 million in September 2007.
In October 2006, O'Quinn pledged $5 million to Texas Democrat Chris Bell for his gubernatorial campaign.
O'Quinn now maintains an extensive collection of cars, with a total value of over $100 million to buy 618 cars, including: seven Duesenbergs; the 1911 Rolls-Royce Silver Ghost featured in the film Titanic; John F Kennedy's 1962 Lincoln Continental Bubble Top limo; a 1937 Bugatti Type 57 Atalante.
In September 2006, he bought: a 2005 Lamborghini Gallardo covered with 33 celebrity autographs ($500,000); the Batmobile used in the filming of Batman Forever ($335,000), a 1941 Packard limousine used by President Franklin D. Roosevelt ($290,000), a 1938 Talbot-Lago ($3,350,000); and a 1938 Cadillac Town Car used by Pope Pius XII ($250,000).
The centre piece of the collection is plain grey 1975 Ford Escort GL, once owned by Polish priest Karol Wojtyla - before he became became Pope John Paul II. Bought at the Kruse auction at SEMA, the car was sold by the Pope at auction for charity to Chicago restuaranter Jim Rich in 1995, who paid $102,000 for the car. O'Quinn paid €690,000 for the car October 2005.
In late 2006, O'Quinn found cars missing from his collection, including a Ferrari 575M and a 1965 Ford Shelby Mustang GT350. O'Quinn tried to get in touch with Zev Isgur, a 32-year-old ex-con whom he'd befriended and entrusted with the management of his collection of classic cars. Isgur was later convicted of embezzlement.