Elizabeth MacDonald said the New York state attorney general’s lawsuit against the Donald J. Trump Foundation is a "scathing rebuke of a sitting president."

Acting Attorney General Barbara Underwood filed the lawsuit Thursday for alleged illegal conduct and “unlawful political coordination” to benefit personal and business interests.

“As our investigation reveals, the Trump Foundation was little more than a checkbook for payments from Mr. Trump or his businesses to nonprofits, regardless of their purpose or legality,” Underwood said in a statement Thursday. “This is not how private foundations should function and my office intends to hold the Foundation and its directors accountable for its misuse of charitable assets.”

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The president fired back on Twitter, blasting the "ridiculous" lawsuit and former Attorney General Eric Schneiderman - who resigned May 7 after allegations of sexual misconduct from multiple women - for spearheading the investigation but not having “the guts” to bring the suit.

On "Outnumbered," MacDonald said these are really serious charges, as charitable foundations are not supposed to be used to resolve personal debts.

She noted that Underwood’s office also sent referral letters to the Federal Election Commission and the Internal Revenue Service, suggesting additional investigation and potential further legal action are warranted.

"This is a scathing rebuke of a sitting president and his foundation," MacDonald said.

She added that she's curious why Trump continues to fight this and refuses to settle, since the investigation has been going on for years and the evidence is mounting.

"I'm not sure it would be wise to continue to fight it. I think he should just settle it and move on."

Underwood is reportedly seeking to dissolve the foundation under court supervision, obtain restitution of $2.8 million, impose additional penalties and ban President Trump from future service as a director of a New York non-profit for 10 years, and ban Trump's children -- Donald Jr., Ivanka and Eric -- from service for one year.

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