Leanna Harris's Attorney Says She Passed a Polygraph Test

Leanna Harris

Kelly Huff/Pool/Reuters/Landov

By Steve Helling

@stevehelling

09/23/2014 AT 06:05 PM EDT

Lawyers for a Georgia woman whose husband is charged with murder in the death of their toddler son in a hot vehicle claim that she passed a privately-administered polygraph test in which she was asked about whether she knew her husband would leave the child in the vehicle, according to Associated Press reports.

Leanna Harris's lawyer, Lawrence Zimmerman, said in an emailed statement to the Associated Press that he hired a licensed veteran polygraph administrator and former law enforcement officer to administer the test to Harris on July 16.

Zimmerman claims that Harris passed the test with no indication of deception. A source tells PEOPLE that the entire polygraph test was videotaped.

Cobb County Police have no comment on the lie detector test, but a source close to the investigation tells PEOPLE that the authorities had no part in administering or verifying the test's authenticity.

According to AP, Zimmerman said that Harris responded "no" to each of the following questions during the polygraph test:

• Prior to June 18th, did you know that your husband would leave your son in that vehicle?

• Did you plan or arrange with your husband to leave your son in that vehicle?

• Did your husband tell you that he was going to leave your son in that vehicle?

Although police have questioned Leanna Harris multiple times, they have not charged her with any crime.

On Sept. 4, a Cobb County grand jury indicted Justin Ross Harris on eight charges, including malice murder, felony murder and cruelty to children. The malice murder charge indicates that prosecutors believe that Harris intentionally left his 22-month-old son, Cooper, in the hot SUV to die.

After the toddler's death on June 18, Justin Ross Harris told police he planned to drive his son to daycare after taking him to breakfast at Chick-Fil-A. According to Harris, he forgot about his son and drove to work instead, leaving him in the hot car.

Harris remains jailed without bond. His attorneys argue that the death was an accident.