After the state rested at her trial, Stubblefield presented two expert witnesses to challenge the assertions made by the state's experts, who have testified D.J. suffers from mental disabilities and cannot consent to sexual activity.Crossley is the facilitated communication advocate whose expert testimony the judge disallowed.
The first defense witness, Robert Trapani, an occupational therapist who evaluated D.J., testified D.J. may have physical impairments, but he is able to make choices in his movements.
Trapani noted how, during his examination, D.J. consistently selected a CD of soul music out of different music CDs available.
"What I felt was that he was making a choice for that particular music," said Trapani, adding that D.J. demonstrated "volitional control."
The second defense witness was Dr. Rosemary Crossley, an expert in augmentative and alternative communication, who testified about a communication assessment of D.J. that was conducted by an expert on behalf of the state.
That evaluation was performed in 2012 by Howard Shane, a speech pathologist at Boston Children's Hospital.
Shane, who testified for the state last week, said he determined D.J. does not understand any symbols, such as pictures and written words. He also said D.J. could not identify letters and could not spell.
But Crossley said she disagreed with Shane's conclusions. While Shane had claimed D.J. has intellectual disabilities, Crossley argued his lack of responses during the evaluation were due to his physical limitations.
"There's no indication to me...that (D.J.) has the motor skills necessary to use the keyboard or to point accurately to letters independently," Crossley told Stubblefield's attorney, James Patton.
Although D.J. grabbed pieces of food during Shane's evaluation, he was not able to grab or point to certain objects. But Crossley attributed that distinction to how D.J. was trained extensively in school to feed himself.
Crossley said it's extremely difficult to transfer those food-related motor skills to pointing to other objects, because such skills are taught to follow a specific pattern.
Crossley also noted in particular that D.J. was sitting in "a regular chair" during Shane's three-hour evaluation and that D.J. was leaning on his brother for support during the assessment.
Crossley said "a stable, seating position is absolutely vital."
Crossley is expected to continue her testimony on Wednesday.
For Stubblefield's trial, Superior Court Judge Siobhan Teare has barred expert testimony on facilitated communication, because she determined it is "not a recognized science." The judge also has warned Stubblefield to not take on an expert's perspective in her testimony about the technique.
Several scientific organizations have declared the technique is invalid.
Crossley — who has been credited with developing the method in Australia in the 1970s — performed her own communication assessment of D.J.
But Teare ruled in February that Crossley could not testify at the trial about her evaluation after the judge found her methods were similar to facilitated communication and that Crossley improperly assisted D.J. during the examination.