BOSTON (Reuters) – A former counselor at a Florida private school pleaded guilty on Friday to secretly taking college placement tests for the children of wealthy parents as part of the largest admissions fraud scheme uncovered in U.S. history.

Mark Riddell, 36, was charged from a role in the scheme that prosecutors said allowed wealthy parents including the actresses Felicity Huffman and Lori Loughlin to use cheating and bribes to help their children secure spots at universities like Yale, Georgetown and the University of Southern California.

Riddell pleaded guilty in Boston federal court to conspiracy to commit mail fraud and conspiracy to commit money laundering, prosecutors said on Twitter. Asked at a news conference in March how Riddell knew the exam answers, U.S. Attorney Andrew Lelling said he was just a really smart guy.

Riddell is among 50 people who prosecutors say participated in schemes to cheat on entrance exams and pay $25 million in bribes over eight years, before a wave of arrests in last months Operation Varsity Blues.

California college admissions adviser William Rick Singer has pleaded guilty to facilitating the cheating scam and bribing coaches to present the parents children as fake athletic recruits.

Prosecutors said that as part of the scheme, Singer arranged beginning in 2012 to have Riddell either secretly take SAT and ACT college entrance exams in place of his clients children or correct their answers.

Singer admitted to advising his clients to seek extra time for their children to take the exams, including by claiming they had learning disabilities, and then have their children take the exams at two test centers he controlled.

He controlled those test centers, a Texas high school and a private college preparatory school in California, by bribing test administrators who would then allow Riddell to proctor the exams and carry out the cheating, prosecutors said.

Riddell, who worked at IMG Academy in Bradenton, Florida, received $10,000 for each students test, prosecutors said.

In exchange, Singers clients paid him $15,000 and $75,000 per test by making donations to his charity, according to prosecutors. Many children were unaware their parents arranged for the cheating, prosecutors said.

The clients included Huffman, who paid to have Riddell in 2017 secretly correct her daughters answers on the SAT, prosecutors said.

Huffman and 12 other parents agreed on Monday to plead guilty to conspiracy to commit mail fraud and honest services mail fraud.

Reporting by Nate Raymond in Boston; editing by Scott Malone, Peter Cooney and Richard Chang

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