Gosnell was arrested in January 2011 and charged with seven counts of infanticide and one count of murder in the case of a Nepalese woman who died during an abortion.
During the trial's fifth week, several patients and former employees testified about the squalid conditions at the clinic described by some as "a house of horrors." Prosecutors were seeking the death penalty against Gosnell.
Common Pleas Judge Jeffrey Minehart did not give a reason for dismissing the three murder counts against the 72-year-old doctor who ran the Women's Medical Centerre in West Philadelphia. The judge's decision preceded the start of defense arguments, which had been scheduled to begin the afternoon of April 23 and were postponed until April 24.
Gosnell still faces four charges of first-degree murder and one charge of third-degree murder related to the death of the patient.
According to The Associated Press, eight former co-workers, including Gosnell's wife, Pearl, earlier pleaded guilty to charges ranging from third-degree murder to racketeering to performing illegal, late-term abortions.
The judge upheld charges that Gosnell violated Pennsylvania's abortion laws by performing abortions after 24 weeks and failing to counsel women 24 hours before the procedure. He also granted a motion for acquittal in five charges of abuse of corpse against Gosnell.
In a statement on the Priests for Life web site, Alveda King, niece of the Rev. Martin Luther King Jr., said she sat in the packed courtroom as three of eight murder charges were thrown out against Gosnell. She said the judge "apparently did not believe based on the evidence presented that three of the babies Gosnell was charged with murdering were viable — that is born alive and killed as prosecutors alleged."
King, director of African-American outreach for Priests for Life and Gospel of Life Ministries, said: "You don't have to be a pro-lifer to know that what this doctor is accused of is wrong."
She noted that the Gosnell case had not received much media attention until recently, but said that in news coverage "reporters seem all too eager to comment and condemn the actions of abortionist Kermit Gosnell but not the system that created him."