Kristin Cavallari accused Jay Cutler of 'marital misconduct' — but what does that mean?

Kristin Cavallari's divorce filing shocked fans nearly as much as this weekend's announcement she and Jay Cutler were separating. The Very Cavallari star accused her husband of nearly seven years of "marital misconduct."

"The Wife would show onto the Court that the Husband is guilty of such inappropriate marital conduct as renders further cohabitation unsafe and improper," the documents state.

So, what exactly does that mean? Yahoo Entertainment consulted with Jillian Gross, a partner with NYC-based family law firm Aronson Mayefsky & Sloan, to understand more.

"In Tennessee, inappropriate marital conduct means a spouse has 'caused pain, anguish or distress to the other party and rendered continued cohabitation improper, unendurable, intolerable or unacceptable,'" she explains.

Gross says "it is a broad definition" that generally means cruel and inhuman treatment, an extramarital affair, sexual misconduct, abusive language or physical abuse.

It’s been speculated Cutler was unfaithful; however, a source close to the former couple tells Yahoo Entertainment that’s false. (A rep for the reality star didn't respond to Yahoo's request for comment.)

Kristin Cavallari and Jay Cutler on Season 2 of Very Cavallari. (Photo: NBCUniversal via Getty Images)

Tennessee is a "fault state," which means someone filing for divorce must prove that the other spouse did something wrong.

"Tennessee courts grant no-fault divorces based on irreconcilable differences if the parties agree to all terms of a divorce," Gross notes. "If the parties do not agree, then the court can either grant a divorce to the party 'less at fault' or determine that both spouses are entitled to a divorce and declare them divorced rather than awarding a divorce to one spouse over the other."

Cutler, who filed for divorce on April 21, cited "irreconcilable differences" as grounds for the divorce. Cavallari, who filed on Friday, cited "irreconcilable differences" and "inappropriate marital conduct."

"In Tennessee, a determination of fault is important. Marital misconduct can have an impact on negotiations over the division of property, provision of alimony and payment of additional child support," Gross continues. "Specifically, the judge in a divorce has substantial discretion, especially in awarding alimony to a spouse."

She adds, "That being said, even if the court grants a divorce based upon one of these types of misconduct, the judge may still choose not to weigh the conduct heavily when determining fault. The court’s decision will depend largely upon the type of the spouse’s misconduct and the severity and persistence of that behavior."

Cutler and Cavallari signed a prenuptial agreement ahead of their 2013 wedding, which he asked to be upheld in his filing. As for whether a spouse's misconduct could have implications on that, Gross says it's unlikely "that fault will play into overturning" a prenup.

"A prenuptial agreement in Tennessee will be upheld if it was entered into freely, knowledgeably and in good faith and without exertion of duress or undue influence upon either spouse," she explains.

"If the couple here is not able to agree on everything — which would likely relate to issues of custody or child support since those would not have been covered under the prenuptial agreement — then one party filing for divorce under a 'fault' ground seems required," Gross adds. "It is possible that the actual basis for the filing is less salacious than the ground would suggest."

Celebrity divorce attorney Christopher Melcher, partner of L.A.-based Walzer Melcher, agrees and speculates "that the legal wording of [Kristin's] divorce petition is being made into something that it is not."

"Kristin explained earlier that, 'This is just the situation of two people growing apart.' That statement is inconsistent with there being misconduct. My sense is that Kristin wants this to be an amicable split," he shares.

In matching statements on Sunday, Cavallari and Cutler revealed "we have come to a loving conclusion to get a divorce."

"We have nothing but love and respect for one another and are deeply grateful for the years shared, memories made and the children we are so proud of. This is just the situation of two people growing apart," they said in their respective Instagram posts.

"It appears Kristin is being careful by asking that the marriage be terminated either by agreement for irreconcilable differences, or by proof of misconduct if Jay does not agree to the divorce," Melcher theorizes. "Mostly likely, he will agree to the divorce and fault will not have to be shown. No celebrity couple wants a public fight over why their marriage ended. It hurts their brand and children. That is why most celebrity divorces are handled quietly, with a joint statement about how they still love each other but just don’t want to be married anymore."

Cutler asked for joint custody in his divorce filing while Cavallari is seeking primary physical custody with the former NFL quarterback being granted visitation.

TMZ reports Cavallari was surprised Cutler filed first and was set off by his claim that he was the "at-home parent" who was the "primary caretaker" of their three children.

"We're told Kristin was shocked and claims Jay was not telling the truth ... she says she has been the primary caregiver," TMZ wrote.

Cavallari declared in her filing, "She denies that Husband has always been the available at home parent and primary caretaker of the parties' minor children. Wife would show that she has been the primary residential parent ..."

The stars have three children together: sons Camden, 7, and Jaxon, 5, and daughter Saylor, 4.

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