The New England Innocence Project is looking at “several” Bay State cases where a person was convicted of murder following a diagnosis of shaken baby syndrome, saying the science behind that conclusion is not sound — the same argument now being made by lawyers for an Irish nanny accused of killing a baby in her care.

“The reason is that the scientific underpinnings of shaken baby syndrome have been called into question,” said Denise McWilliams, executive director of the project. “There’s a good amount of evidence that shaken baby syndrome might, at best, be questionable and it might, at worst, be totally bogus.”

McWilliams would not discuss which cases the Innocence Project was looking at, but said there is a growing chorus of experts nationwide casting doubt on the diagnosis. At issue is whether the injuries normally associated with shaken baby syndrome — brain bleeding, retinal hemorrhaging and brain swelling — can be inflicted without leaving a mark on the child, or harming the child’s neck, which is what is alleged in some cases, she said.

Lawyers for Irish nanny Aisling Brady McCarthy, who is charged with first-degree murder in the death of 1-year-old Rehma Sabir, on Thursday in court filings challenged the shaken baby diagnosis made by Dr. Alice Newton, saying the child had a series of medical problems that weren’t examined as potential causes of death and Newton relied on techniques that are coming under fire from the scientific and medical community.

But Jetta Bernier, executive director of MassKids, a nonprofit child welfare group, said the purported scientific doubt is just courtroom theatrics and is not based on the years of research she’s seen.

“There is overwhelming support in the medical community that this is a real syndrome and they understand it,” Bernier said. “In this particular case we have two of the classic symptoms. It was totally appropriate for her to make this claim given the extent and type of injuries.”

Bernier defended Newton, who sparked controversy when her abuse diagnosis led 16-year-old Justina Pelletier to be placed in foster care after her parents questioned a doctor’s treatment plan. In June, a judge restored their parental rights.

“She has a reputation in the medical community as being a very competent and caring pediatrician,” Bernier said. “She has seen hundreds and hundreds of abused children in her practice over the years. She has probably seen dozens of shaken baby cases in her career. The defense lawyers keep coming up with the same arguments again and again. … This is a settled scientific fact.”