David Matusiewicz and mother Lenore Matusiewicz accomplices in Delaware courthouse shooting,

Thomas Matusiewicz opened fire Monday in the New Castle County Courthouse, killing Christine Belford and her friend Laura Mulford and injuring two Capitol Police officers before taking his own life, according to Delaware State Police.

State police have not filed charges, but in a search warrant served Tuesday, investigators listed David Matusiewicz and his mother, Lenore, as willing accomplices in the slayings. It was reported early on that David was the shooter.

Christine Belford

Now a hearing will be set to review the firearms recovered and if the pair are accomplices in the murder of Christine Belford and her friend Laura Mulford.

In the family’s house and a storage locker in Hidalgo County, Texas, police found 13 guns; hundreds of rounds of ammunition stashed in boxes, jars, and plastic bags; court papers; and books titled Kill All the Lawyers and New I.D. in America, according to documents.

The weapons were checked against federal and state databases and came back clear and Lenore and Thomas Matusiewicz reported in bankruptcy filings that they owned only one firearm – a 9mm Glock.

Lenore Matusiewicz, who in 2007 helped her son kidnap his three daughters, defended her family in an interview Wednesday with 6ABC. She denied that she and her son knew what her husband was going to do.

“I wish I had known. Maybe I could have done something to stop it,” she said, crying. “I would have stepped in front of the gun; I didn’t want anybody dead.”

The search warrant cites surveillance footage that shows father and son hugging in the courthouse lobby before the shooting. David Matusiewicz then goes through security into the courthouse, while Thomas Matusiewicz waits in the lobby for 35 minutes until Belford arrives, police said.

Lenore Matusiewicz told 6ABC that her husband and son were affectionate and hugged often. She also said her husband suffered from a brain tumor “in the area [that] controls reasoning, memory, judgment, decision-making – all of the higher functions. And it changed him.”

In various court filings, Thomas and Lenore Matusiewicz accused Belford of abusing the children and expressed frustration with a perceived lack of justice in the courts.

The court will also be reviewing if the firearms violated David Matusiewicz parole from his previous kidnapping case of his children.