Thinking of helping out your inebriated friends by volunteering as a designated driver? You might want to rethink such an act of automotive altruism. According to a report in The Globe and Mail, a lawsuit launched by a woman who leapt from a moving car during a domestic squabble might make people ponder the merits of being a designated driver.

Indeed, the lawsuit - which is headed to trial - could set a precedent by making designated drivers liable for intoxicated passengers who cause themselves harm.

The details: the plaintiff, Inga Richardson, jumped out of a moving car after fighting with her common-law spouse. As a result, she suffered severe brain damage and injuries to her body after bouncing along the blacktop of a three-lane artery in Oshawa, Ont.

Her lawyers, David MacDonald and Adrienne Kirsh, allege in a statement of claim that Richardson's partner, Joey Sanayhie, should've supervised her consumption of alcohol and prevented her from harming herself on the way home. The legal eaglets contend Sanayhie knew Richardson was prone to leaping from speeding vessels (she once jumped off a moving boat after becoming agitated.)

While designated drivers play a vital role in society, MacDonald says they must act responsibly. (Apparently, this includes possessing clairvoyant powers of The Amazing Kreskin in order to second-guess the actions of one's drunken passengers.)

However, Sanayhie's lawyers, John J. Adair and Greg Abogado, maintain individuals won't likely agree to be designated drivers if they're going to be on the hook for those passengers who decide to bring harm to themselves. "This [a legal victory for Richardson] is a development that clearly would not be in the public interest," says Adair.

Recently, Sanayhie won at least a partial victory when an Ontario Superior Court judge threw out a portion of Richardson's claim. He ruled that a designated driver cannot be held responsible for how his passengers behave at a social event prior to getting into a vehicle. However, the judge noted the critical question of whether Sanayhie was responsible for ensuring Richardson's safety on the way home will be decided at a trial.

If Richardson is indeed successful, designated driving might be joining Happy Hour on the scrapheap of obsolesce. Let's hope sanity prevails...