HARTFORD, Conn. (WTNH) — The estranged husband of missing mother Jennifer Dulos is due in court Tuesday in Hartford.

This time, Fotis Dulos faces a civil trial brought against by his mother-in-law, Gloria Farber, who claims Dulos owes her $2.5 million.

The missing New Canaan woman’s mother said Dulos owes the money back in payments for loans she claims helped finance his business. 

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It’s the first time Dulos will testify under oath since his wife disappeared in May.

“The money that Mrs. Farber, the mother, is looking for is sizable and she has some very heavy-hitting witnesses, including Bill Cosby‘s former lawyer,” said legal expert Tara Knight. “So, this is not something they are treating lightly, they are going after Mr. Dulos and they are seeking to have him, I’m sure, testify in some capacity.”

The civil lawsuit is separate from the looming criminal charges against Farber Dulos’ estranged husband.

“In criminal cases, the prosecution has to prove that you are guilty of the charge without a reasonable doubt it’s a very hefty burden,” Knight said. “In a civil case, Mrs. Farber only has to prove that it’s more likely than not that he owes that money to her.”

Related: State police release detailed documents in Jennifer Dulos’ disappearance

Knight told News 8 there are some distinct differences to watch out for in a civil case versus a criminal case. Those differences may boil down to the rights of a plaintiff.

“In a criminal case, Mr. Dulos has the right to remain silent. He has the right not to answer questions. That does not happen in a civil case, if you bring a civil case or if you’re sued, you do not have the right to remain silent. In fact, if you remain silent in a civil case and say ‘I’m not testifying because I have the right to remain silent and not incriminate myself,’ that invocation of that right can be used against you in a civil case.”

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Knight said there are two things to watch out for in this civil trial: “If I were watching this civil case, what I would look for is to see what and if Mr. Dulos takes the stand, and number two, to what extent the judge allows the plaintiff, meaning Mrs. Farber’s side, to ask questions that are not really relevant or germane to the issue of the money, but maybe seek information outside of that to try and gather information about the criminal charges that are pending.”