A Monaco judge has granted full custody of Hermes, 9, and Helena, 6, to Rutherford's ex-husband Daniel Giersch, according to leaked documents obtained by the Daily Mail.
Moving forward the children – who have lived with their father in Monaco and France since 2012 – will remain with Giersch and, while the parents must make decisions concerning their kids' lives jointly, Rutherford is "only permitted to 'exercise her visiting and accommodation rights exclusively in France and Monaco.' "
New York-based lawyer Susan Moss, a partner at Chemtob Moss & Forman who is not involved with Rutherford's case, tells PEOPLE that, after Rutherford's appeals in both California and New York state were denied, "What the Monaco court is doing is saying, 'We have jurisdiction, and we want to keep it.' "
As a result, Giersch maintains the court-appointed right of sole custody over the children that was most recently upheld by a New York judge after Rutherford refused put Helena and Hermes on a plane to Europe at the end of their summer vacation, telling PEOPLE exclusively at the time that they "got really panicky" and cried about leaving.
In August, German businessman Giersch, 47, denounced the controversial decision as kidnapping and, Moss says Tuesday's finding is a direct result of Rutherford's unexpected move.
"[Rutherford's] visitation rights can only be used in France and Monaco, and the reason for that is because, this summer when she had visitation in America, she refused to return the kids, and courts really don't like self-help," says Moss.
"Kelly Rutherford has only herself to blame," she adds. "She is the reason why she lost custody of these kids."
Michael Stutman, Head of Family Group at Mishcon de Reya New York, who also has not worked with Rutherford or Giersch, agrees with Moss's assessment: "The actions of Ms. Rutherford leading up to this ruling make the decision to award custody to Mr. Giersch the furthest thing from a surprise," he says.
Adds Stutman, "Ms. Rutherford essentially had her head handed to her because she tried to take the law into her own hands."
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Just another step in a six-year custody battle, the Monaco court's decision awarded this week Rutherford a monthly sum from Giersch, but it limits her possible visitation period with the children to half of their Christmas, spring and summer vacations while giving her visitation rights during all of France and Monaco's All Saints' Day (a short autumn break).
An attorney for Rutherford declined to comment when reached by PEOPLE, but Rutherford, 41, told PEOPLE in August: "My children ask me all the time if I am still fighting for them. ... I always tell them the day will never come when I say no."
Rutherford has been sharing pictures of her children on Instagram in the months since September's decision and fighting as if regaining her custody is still in sight – but Moss fundamentally disagrees with that motivation.
"Has she lost custody?" she notes. "I mean, it's hard to lose what you don't have. But if anyone thought she had physical custody of these kids, she's lost it. ... And she lost custody from the original California ruling, not from this. She never had custody. She hasn't had custody in years."
And Stutman has a few final words as Rutherford and her legal team as they face another crushing defeat: "Any responsible lawyer would advise her to end this crusade for custody."