PHILADELPHIA – A judge tossed three of eight murder charges Tuesday in the trial of an abortion doctor accused of killing babies who prosecutors say were born alive at a clinic they dubbed “a house of horrors.”

Dr. Kermit Gosnell, 72, still faces the death penalty if convicted on four remaining counts of first-degree murder involving babies he’s accused of killing with scissors after they were born alive. He also faces one count of third-degree murder in the death of a patient at a medical center.

Judge Jeffrey Minehart did not explain why he dismissed the three murder counts, but apparently felt he had not heard sufficient evidence from prosecutors that those three babies were viable, born alive and then killed. Much of the evidence during the five-week prosecution case has come from the recollections of former staff members, though their testimony was bolstered by graphic photographs of some of the aborted babies.

Prosecutors argued that the babies were viable and that Gosnell and his staff cut the backs of their necks to kill them.

“Why would you cut a baby in the back of the neck unless you were killing it?” Assistant District Attorney Ed Cameron asked.

The defense questioned testimony from staffers who said they had seen babies move, cry or breathe. Defense lawyer Jack McMahon argued that each testified to seeing only one movement or breath.

“These are not the movements of a live child,” McMahon said. “There is not one piece — not one — of objective, scientific evidence that anyone was born alive.”