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Lori Loughlin[1]'s husband practically admitted to paying big bucks to get their daughter into USC ... according to prosecutors.

In the indictment that brought a new charge upon Lori and Mossimo Giannulli, he's accused of emailing their accountant admitting to working the system to get their daughter admitted.

According to the docs ... Mossimo forwarded a $200,000 invoice he got from Rick Singer to his accountant for payment in April 2017 and wrote, "Good news my daughter...is in [U]SC... bad is I had to work the system."

Prosecutors claim on or about the same day, the daughter received a formal acceptance letter from USC and Mossimo wired the money.

As we reported ... the U.S. Attorney out of Boston filed a new charge[2] of Federal Program Bribery against the couple Tuesday. The 2 allegedly paid $500,000[3] to the mastermind, Singer, to get their daughters into USC ... and this $200k is allegedly part of that total.

The new charge carries a maximum 5-year prison sentence. They've already charged Lori and Mossimo with various other crimes[4] that could land them in prison for 40 years.

Of course ... they could also possibly cop a plea deal[5].

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