Accused Gilgo Beach serial killer Rex Heuermann appeared in court for a hearing Tuesday. He has pleaded not guilty to the murders of at least seven women over 30 years.

The judge ruled Tuesday that all seven murder cases will be tried together.

The defense had wanted to split the cases, arguing the modus operandi differ and that jurors wouldn't be able to separate evidence.

"The judge ruled against us. We don't like the decision. We don't agree with the decision," defense attorney Michael J. Brown said.

It was a victory for the prosecution, which pointed to Heuermann's so-called murder manifesto.

"Those magical legal words -- 'inextricably interwoven,'" Suffolk County District Attorney Raymond Tierney said.

Advanced DNA testing can be used, judge reaffirms

Earlier this month, the judge ruled that evidence acquired using cutting-edge advanced DNA testing can be used at trial. It's the first time such evidence can be admitted. The judge reaffirmed that decision Tuesday. 

Prosecutors say whole genome testing ties Heuermann to six of the victims. The defense challenged that decision, saying it is in violation of public health law since the lab involved isn't licensed in New York. Heuermann's attorneys have called the process "magic."

"It's a dizzying amount of information -- seven murders that span from 1993 to 2010. We'll have over 100 witnesses coming in from 15 different states," Tierney said.

"This is a mountain of mountains. You've got to remember we are talking about 30 years of investigation. We are talking about seven victims," Brown said.

The case against Rex Heuermann

Heuermann was arrested in July 2023. Since then, he has been hit with additional charges.

He is accused in the murders of seven women, dating back to 1993. Investigators suspect he may be linked to more killings.

Prosecutors say DNA testing matched Heuermann to hairs that were found on belts, tape and burlap around his alleged victims.

Heuermann has denied it all. His attorney has rejected any idea of a plea deal, saying Heuermann is looking forward to his day in court.

Asked what his client's current mood is, Brown said, "Well, he's in a cell contemplating the rest of his life, maintaining his innocence."

Heuermann's ex-wife, daughter make appearance in court

Asa Ellerup, who refuses to believe her ex-husband committed the crimes, walked into court with their daughter, Victoria Heuermann, who has said she thinks her father is guilty.

"She most likely believes that her father is the Gilgo Beach serial killer," said Robert Macedino, their attorney.

Macedino said his clients plan to attend all court proceedings and will continue to visit Rex Heuermann in jail.

Rex Heuermann is next due back in court on Jan. 13 for a hearing on discovery materials.