BOSTON – Twelve defendants, including six former college athletic coaches and two test administrators, on Monday each pleaded not guilty to racketeering conspiracy charges in federal court for their alleged roles in the nation’s largest-ever college bribery scheme.

The 12 defendants were arraigned Monday before Magistrate Judge M. Page Kelley as they made their first appearance in a federal court in Boston, where the nationwide case is being tried by the Justice Department.

One by one, the defendants and their attorneys stood up and were told their rights, beginning with Gordon Ernst, the former head tennis coach at Georgetown University, who is accused of taking more than $2.7 million in bribes to designate at least 12 recruits as tennis players including some who did not even play the sport.

"Not guilty," each of them said individually when asked for their plea.

If they're convicted, each faces a maximum penalty of up to 20 years in prison, $250,000 in fines and 3 1/2 years of court supervision. While the case is pending, the defendants' travel is restricted to within the United States, among other conditions.

Each is currently out on bail. The judge set a status conference hearing for June 3.

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Federal prosecutors say that rich and powerful parents of underqualified students paid $25 million collectively since 2011 to William "Rick" Singer, who led a sham nonprofit, to either have someone cheat on their ACT or SAT exams or to pay off athletic coaches who accepted their children on their teams even if they didn't play the sport. Singer has already pleaded guilty to racketing conspiracy, money laundering conspiracy and other charges.

Those who pleaded not guilty Monday included four former employees of the University of Southern California: Donna Heinel, the school's onetime senior associate athletics director; Ali Khosroshahin, a former women's soccer head coach; Laura Janke, a former assistant soccer coach; and Jovan Vavic, a former legendary water polo coach.

Not-guilty pleas also came from Bill Ferguson, former volleyball head coach at Wake Forest University; former UCLA men's soccer coach Jorge Salcedo; Niki Williams and Igor Dvorskiy, both ACT and SAT test administers accused of accepting bribes to allow cheating on the exams; and two individuals, Mikaela Sanford and Steven Masera, who prosecutors say worked with Singer, the alleged ringleader of the cheating and bribery scheme.

Fifty people have been charged overall in the sweeping federal case, and Monday's hearing is a sign that many could dig in for a legal fight.

"Two weeks ago the US Attorney told you about a litany of abuses - phony test scores, unqualified students, falsified athletic profiles," Shaun Clarke, attorney for former Wake Forest University women's volleyball coach Bill Ferguson, said following the court hearing.

"Well, I can't speak to what happened at other schools, but not at Wake Forest University. No one was admitted to Wake Forest who didn't earn it, as a student and as an athlete. Bill Ferguson doesn't belong in this indictment."

On Friday, an additional 23 defendants, all parents accused of crimes in the case, are scheduled to appear in federal court in Boston. The group was originally set to include the case's two highest-profile defendants, actresses Felicity Huffman and Lori Loughlin, but their court appearances are now scheduled for April 3.

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A judge granted requests for different court dates from both women as well as Loughlin's fashion-designer husband, Mossimo Giannulli, last week. They cited scheduling conflicts.

Loughlin and Giannulli are accused of paying bribes of $500,000 to get their daughters in to the University of Southern California. They had originally asked for a delay until the week of April 15, but that request was denied.

Huffman is accused of paying $15,000 that she disguised as a charitable donation so that her daughter could take part in the entrance-exam cheating scam.

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Huffman, Loughlin and Giannulli each appear before U.S. District Court Judge Page Kelley.

The defendants who appeared Monday are each of those charged by indictment. Most of the 33 parents accused of paying to cheat or lie their way into college have been charged in a separate complaint.

An additional four defendants, including Singer and Mark Riddell, who allegedly took tests for students, have been charged individually by information.

Here's who appeared in federal court Monday and pleaded not guilty. Some are no longer in the positions they had when they allegedly committed the crimes.