(Image Credit: ABC News)

A civil suit against a polo magnate who adopted his girlfriend in an apparent effort to protect some of his fortune has been settled, ABC News has learned.

Multi-millionaire John Goodman was sued by Lili and William Wilson for up to $100 million for the wrongful death of their son, Scott.

Goodman allegedly ran a stop sign in February 2010 and smashed his Bentley into Wilson's Hyundai. He  fled the scene on foot, according to police reports, leaving the 23-year-old to drown in a nearby canal. On a 911 call after the accident, Goodman tells an operator that he was "down the road to a barn."

It was determined that Goodman's blood alcohol level was more than twice the legal limit, police documents state.

Sources declined to discuss the details of the civil settlement.

The settlement came just as Goodman's criminal trial is about to begin. Opening statements in the trial are scheduled to  begin on March 13.

He faces charges of DUI manslaughter, vehicular homicide and leaving the scene of a crash. If convicted, he could spend up to 30 years in prison.

The tycoon's legal woes attracted attention in October when he adopted his longtime girlfriend, socialite Heather Hutchins, 42, in an apparent maneuver to shield one-third of his fortune from the Wilsons' lawsuit.

Neither of his two children are 35 years old, the age they are given access to the family trust.

In total Hutchins could receive as much as $200 million over the next 40 years.

ABC News' Christina Ng contributed to this report