Originally Published: 25 APR 19 22:06 ET

Updated: 13 MAY 19 16:21 ET

By Chloe Melas, CNN

(CNN) -- Actress Lori Loughlin and her husband, Mossimo Giannulli, maintain they are innocent of the charges against them in the college admissions scandal.

"This is not a story. This has become a total circus. They didn't do anything wrong," a source close to the couple told CNN.

Giannulli and Loughlin have both pleaded not guilty to charges of conspiracy to commit fraud and conspiracy to commit money laundering. Each of the charges is punishable by up to 20 years in prison.

Prosecutors say Loughlin and Giannulli paid $500,000 to a fake charity to get their two daughters accepted into the University of Southern California, falsely designating them as crew team recruits.

Defending the couple's alleged actions, the source said, "They did what so many people in their financial situation do to get their kids into schools. What about the people that donate buildings to schools? Why are they becoming the poster children for things that have been going on forever? They didn't do anything illegal. They just wanted a good education for their kids, like every parent does."

"There was no bribe," the source added. "They are solely focused on winning their legal case."

On Thursday, the University of Southern California announced in a letter that it will change the admissions process for prospective student-athletes under consideration for the 2019-2020 academic year.

"Every student-athlete candidate's file will be reviewed on three levels -- by the head coach, the senior sports administrator overseeing the team, and the USC Office of Athletics Compliance -- before being sent to the admissions staff. The head coach will certify in writing that the student is being recruited for athletic abilities. Athletic rosters will be audited at the beginning and end of every academic year and cross-checked with admissions lists."

The letter also addressed currently enrolled students who have been caught up in the scandal, stating those students have been notified of a review process that's underway and given a deadline to respond. "The possible outcomes range from no finding of violation to revocation of admission, and will depend on the facts of each case," the letter states.

The move comes two days after Laura Janke, the 36-year-old former assistant women's soccer coach at USC, who, according to prosecutors, created fake athletic profiles for the children of wealthy parents, including Loughlin's daughter Olivia Jade Giannulli, agreed to plead guilty.

CNN's Stephanie Becker contributed to this report.