'Really Smart Guy' Mark Riddell Who Aced Exams for Teens in College Admissions Scandal Speaks Out

As the nation’s largest college admissions scam continues to unfold, authorities are revealing the involvement of a professional test-taker, Mark Riddell, who was paid up to $10,000 each time he took or doctored a college entrance exam for the children of lawyers, actresses, business leaders and more, according to court documents.

For at least seven years, Riddell, 36, a Florida prep school administrator, either secretly took college entrance exams — including the ACT and SAT — for students or swapped out the children’s responses for his own, according to a criminal complaint.

“He did not have inside information about the correct answers,” Boston U.S. Attorney Andrew Lelling said during a Tuesday news conference. “He was just smart enough to get a near-perfect score on demand, or to calibrate the score.”

Lelling added: “He was just a really smart guy.”

Sometimes the students were unaware of the deception, with Riddell filling in the test’s bubbles on his own, the complaint states. Other times, he sat with the students, actively participating as they took the exams. On at least one occasion, Riddell allegedly studied a student’s handwriting so he could imitate it as he took the ACT exam for the student in a Houston hotel room. That student was the son of Beverly Hills-based marketing CEO and author Jane Buckingham.

Lelling said that admissions consultant William “Rick” Singer, 58, discussed with parents the test score they wanted for their child and then instruct Riddell to “attempt to get that score, and he was just good enough to do it.”

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Riddell has been charged with conspiracy to commit mail fraud and honest services mail fraud along with conspiracy to commit money laundering. Riddell, a Harvard graduate and former tennis pro, served as exam preparation director at IMG Academy in Bradenton.

In a statement through his lawyer, Riddell tells PEOPLE that he takes “full responsibility” for his actions.

“I want to communicate to everyone that I am profoundly sorry for the damage I have done and grief I have caused those as a result of my needless actions,” the statement reads. “I understand how my actions contributed to a loss of trust in the college admissions process.

“I assume full responsibility for what I have done. I do, however, want to clarify an assertion that has arisen in the media coverage. I absolutely, unequivocally never bribed anyone, nor has the Information filed by the U.S. Attorney’s Office charged me with any form of bribery.

“I will always regret the choices I made, but I also believe that the more than one thousand students I legitimately counseled, inspired, and helped reach their goals in my career will paint a more complete picture of the person I truly am.”

Federal court records unsealed Tuesday in Boston accuse 50 people — including actresses Lori Loughlin and Felicity Huffman — of taking part in a nationwide college admissions cheating scam, according to a release from the U.S. Attorney’s Office in Massachusetts. From doctoring photos to writing large checks, court documents reveal the lengths to which parents went to get their children into universities including University of Southern California, Yale, Georgetown, and Stanford.

Some individuals named in the court documents allegedly paid bribes of up to $6 million to get their children into these elite colleges, according to federal prosecutors.

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Authorities said Singer served as the mastermind behind the massive scam. He employed Riddell and helped facilitate test the test deception for Felicity Huffman‘s daughter, Sofia Grace, 18.

“[Singer] offered a variety of cheating options as part of a widespread conspiracy to enrich himself while also facilitating cheating on SAT and ACT exams, recruiting applicants on the competitive athletic teams in exchange for bribes and concealing the nature and source of those bribes,” Lelling said during the news conference.

According to a complaint, Singer bribed test administrators to allow Riddell to secretly take the ACT and SATs in place of the students. He even allegedly instructed parents to claim their children had learning disabilities so test administrators would allow them to take the test alone or under the supervision of a test administrator and allot them an extended amount of time to take the test.

He allegedly funneled bribes through his nonprofit organization, Key Worldwide Foundation (“KWF”).

Singer on Tuesday pleaded guilty to racketeering, money laundering, tax evasion and obstruction of justice, according to USA Today. He admitted his wrongdoing in court, saying, “All of those things, plus many more things, I did.”

“I was essentially buying or bribing the coaches for a spot,” Singer said. “I created a side door.”