Judge Donald Allen Jr. found there was enough evidence to warrant a trial for Dr. Larry Nassar on charges of first-degree criminal sexual conduct.
Separately, dozens of women and girls - many of them gymnasts - have come forward and accused Nassar of molesting them when they went to him for treatment as far back as the 1990s. He is also facing federal child porn charges.
WHO IS NASSAR?
Nassar, 53, received a medical degree from Michigan State in 1993 and returned to teach and become doctor for the women's gymnastics team. More than 80 percent of his patients were gymnasts, dancers and cheerleaders, including many who didn't go to MSU.
He also was a doctor for nearly 30 years with Indianapolis-based USA Gymnastics, which trains Olympians. He attended team camps and meets all over the world. Nassar quit in 2015 after an internal investigation related to a female athlete's concerns about him.
The organization went to federal authorities a month after the investigation began, not immediately as it had previously stated. The timeline was changed after a report in The Wall Street Journal.
Nassar hasn't commented directly, but his lawyers have denied the allegations against him.
WHAT ARE THE CRIMINAL CASES?
Nassar faces charges in two cases so far, although they're not related to his work with athletes.
The 25-year-old woman who testified Friday said her parents were friends with Nassar and that he repeatedly abused her from age 6 until age 12 during family visits to his home in Holt, near Lansing. She said he rubbed his genitals on her and digitally penetrated her, among other things. She said Nassar later denied it.
"My parents chose to believe him over me," she told the judge.
The woman talked to police last year after seeing a newspaper report of similar allegations against Nassar. Police are investigating more abuse complaints. There is no statute of limitations in Michigan for certain sex crimes committed after 2001.
In federal court, Nassar is charged with possessing thousands of images of child pornography and trying to destroy possible evidence.
"Either you've got it or you don't. It's very difficult to fight and the penalties are severe," former federal prosecutor John Smietanka said of child porn charges.
WHAT IS HAPPENING AT MICHIGAN STATE?
Nassar, who had a campus clinic, was fired in September. Women's gymnastics coach Kathie Klages suddenly quit Wednesday, a day after she was suspended for defending Nassar during a team meeting months ago.
In lawsuits against the doctor, at least two women said Klages downplayed their complaints about him when they were part of a gymnastics youth group at MSU in the late 1990s. An attorney for the coach said Klages would never put athletes in "harm's way."
MSU said it had received only two formal complaints about Nassar, including one in 2014; no charges were filed then. A second complaint last summer led to a broader police investigation, which is ongoing. President Lou Anna Simon recently called Nassar's behavior "criminal and repugnant." An internal review is being led by Patrick Fitzgerald, a former Chicago federal prosecutor.
"If anybody thinks this stops at the gymnastics coach, they're smoking some pretty good dope," said John Manly, an attorney for more than 40 women or girls who are suing Nassar or are planning to do so. "Sexual abuse of this magnitude doesn't happen in a vacuum."
WHAT IS THE STATUS OF THE LAWSUITS?
More females who say they're victims have been added to lawsuits each week. The largest case is in federal court in western Michigan, and it names Nassar, MSU and USA Gymnastics as defendants.
USA Gymnastics won't comment on specific allegations, but it says it's "appalling that anyone would exploit a young athlete or child in this manner." The lawsuits accuse MSU of failing to do more to prevent assaults.
The school also won't address specific allegations. There is an ongoing internal review of all aspects of Nassar's work.
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