Koon was released on a $55,000 unsecured bond. A court date is scheduled for Dec. 27.
"We're glad that he is facing some pretty significant charges and that he's likely to serve jail time," said Anne Reid, Will's mother, who works as treasurer of Moravian College in Bethlehem. "I'm sorry he made some very, very bad choices, but he does need to pay for those choices, and I think jail is the only way."
Reid said she doesn't believe Koon meant to hurt anyone. He'll live the rest of his life knowing he was responsible for two deaths - and for inflicting terrible grief on two families, she said.
"We were victims of his bad decisions," Reid said.
Will and Jamie Reid were passengers, traveling to the Asheville airport after attending a friend's wedding, when Koon's 2003 Lincoln Town Car veered off I-26 and struck a tree.
Jamie, 25, was killed in the crash, and Will, 26, died at Mission Hospital in Asheville later that day. Jamie was pregnant with the couple's first child.
Her father, Ron Soukup, declined to comment on the charges against Koon.
Jamie Soukup and William Reid came separately to Philadelphia in 2010 to join Teach for America, and met while earning master's degrees in urban education at the University of Pennsylvania. Will taught sixth-grade math at People for People Charter School on North Broad Street. Jamie was teaching seventh-grade English and literature at the Harrity campus of Mastery Charter School in West Philadelphia.
They wed May 26 at the College of Physicians, choosing that site because, as the home to the Mütter Museum's collection of medical oddities, it reflected their sense of fun and weirdness.
Their deaths provoked an outpouring of grief from scores of friends and family members in the Philadelphia region and across the country.
On Tuesday, Anne Reid described her family as doing all right, too aware that the holidays will be emotionally bruising and trying to be as positive as they can.
"Bitterness does nothing but eat you up," she said.
She has heard from people who were close friends with Will and Jamie - and from others who never met them but were moved by their deaths.
Reid was contacted by a Willingboro woman, who said she'd been married 50 years, and "if I could give them some of my years, I would."
"You have to take comfort," Reid said, "that they touched people's lives."