Earlier this month, prosecutors sought to get the supermodel subpoenaed to appear as a witness about claims that Taylor gave her "blood diamonds" during a reception in South Africa in 1997.
Taylor's lawyers called the evidence "tangential to the real issues" against the former Liberian president and added that it was too late to introduce it to the trial 15 months after they closed their case.
"For the prosecution to present such inferential evidence at this advanced stage, as part of an obvious publicity stunt, would bring the administration of justice into serious disrepute," Taylor's British lawyer, Courtenay Griffiths, wrote to judges.
Prosecuters want Campbell, who told prosecutors through her lawyer that she did not want to get involved in the case, to testify about an alleged gift of diamonds that Taylor gave her.
Mia Farrow — who visited the home of South African President Nelson Mandela at the same time as Campbell and Taylor — told prosecutors she heard Campbell describe receiving a "huge diamond" from Taylor in the middle of the night.
According to prosecutors, Campbell's testimony would provide "direct evidence of the accused's possession of rough diamonds from a witness unrelated to the Liberian or Sierra Leone conflicts."
Taylor is charged with 11 counts of counts of murder, torture, rape, sexual slavery and the use of child soldiers and terrorism in his role backing rebels in Sierra Leone's 1991-2002 civil war where an estimated 500,000 people allegedly were victims of killings, systematic mutilation and other atrocities.