NEW YORK (CNN/Money) - Merck's legal defense team appealed the decision of a Texas judge who is allowing a former medical examiner to testify before the jury in the first of thousands of Vioxx lawsuits.

Merck's lawyers on Friday filed an appeal with a Texas appellate court in Houston, stating that the trial court "abused its discretion" and made an error in "allowing an unidentified and untimely designated expert witness to testify." The court did not accept the appeal, according to a legal spokesman for the defense, so Merck lawyers filed a second appeal with the Texas Supreme Court in Austin.

The defense lawyers are appealing the Thursday decision of Judge Ben Hardin, who is allowing trial testimony of former Texas medical examiner Maria Araneta in a wrongful death suit filed by Carol Ernst. The plaintiff's husband, a Vioxx patient, died in 2001. Ernst sued Merck in Texas Superior Court because she blames Vioxx for her husband's death.

Araneta signed the autopsy forms for the death of the plaintiff's widow. W. Mark Lanier, the lawyer representing Ernst, paid Araneta's expenses in transporting her from the United Arab Emirates, her current home, to Angleton, Texas, where the trial is being held.

Araneta's testimony could be crucial to the case, which could hinge on Ernst's cause of death.

Merck's lawyers have attacked Lanier's use of Araneta as a witness because she was not on the required witness list. They have also attacked "inconsistencies" in her previous testimony before the judge and lawyers.

"We wanted to raise these issues with the appeals court," said Merck lawyer Jonathan Skidmore, according to legal defense spokesman Kent Jarrell. "There are inconsistencies in the coroner's story."

In response to the appeal, the plaintiff's lawyer Lanier said, "Funny that Merck doesn't want the jury to hear about the cause of death."

Merck & Co., Inc. (down $0.23 to $31.06, Research), based in Whitehouse Station, N.J., is one of the world's largest drug makers with $22.9 billion in 2004 sales. Merck withdrew its blockbuster arthritis painkiller from the market on Sept. 30, 2004, citing health concerns. Since that time, more than 4,100 lawsuits have been filed against the company.

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