By Nate Raymond and Jonathan Stempel

BOSTON A U.S. appeals court on Monday upheld the conviction of a former senior executive at the private equity firm TPG Capital for participating in a vast U.S. college admissions fraud scheme by paying $50,000 to rig his son's college entrance exam results.

The 1st U.S. Circuit Court of Appeals in Boston rejected William McGlashan's argument that the indictment against him should have been dismissed because inflated ACT test scores cannot support the wire fraud charge underlying his conviction.

While McGlashan had pleaded guilty in 2021 to a wire fraud count and has already served a three-month prison sentence, he preserved the right to withdraw his guilty plea if the appeals court agreed that the trial judge should have tossed the case.

Circuit Judge Jeffrey Howard, however, wrote for a three-judge appeals court panel that McGlashan's plan "proved much more intricate than merely tampering with the scores," as it also involved securing a test proctored by an associate of the admissions scheme's mastermind, William "Rick" Singer.

A lawyer for McGlashan did not immediately respond to a request for comment.

McGlashan, a former star portfolio manager at TPG Capital, was among dozens of people charged in 2019 in the "Operation Varsity Blues" investigation.

The probe exposed how some wealthy parents went to extreme lengths to secure spots for their children at prestigious schools including Yale, Georgetown and the University of Southern California.

Singer, a California admissions consultant, admitted to facilitating cheating on college entrance exams and funneling money from parents to corrupt university coaches, to secure the admission of children as fake athletic recruits.

He was sentenced in January to 3-1/2 years in prison. More than 50 people pleaded guilty, including the actors Lori Loughlin and Felicity Huffman, who were among Singer's clients.

The 1st Circuit in May overturned the fraud convictions of two parents who were found guilty in the first Varsity Blues trial - private equity executive John Wilson and former casino executive Gamal Aziz.

Wilson faces a resentencing next month on a tax-related charge.

(Reporting by Jonathan Stempel in New York and Nate Raymond in Boston; Editing by Matthew Lewis)