Yong Kim / Philadelphia Daily News via AP file Dr. Kermit Gosnell is interviewed by the Philadelphia Daily News at his attorney's office in Philadelphia In in 2010.

It took the prosecution five weeks to present their case against West Philly abortion doctor Kermit Gosnell and it took defense attorney Jack McMahon a couple of hours to knock a big hole through a critical part of their argument.

Three first-degree murder charges were dropped against Gosnell after McMahon argued that "there is not one piece...of objective, scientific evidence that anyone was born alive" at Gosnell's clinic.

Prosecutors have argued that the babies were viable and that Gosnell and his staff cut them in the back of the neck to kill them.

Gosnell was originally charged with eight counts of murder. Seven first-degree murder charges are for accusations that he killed seven newborns. The third-degree murder charge is for the 2009 death of Karnamaya Mongar, a 41-year-old Bhutanese refugee prosecutors say received lethal doses of sedatives and painkillers at the clinic while awaiting an abortion.

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He also is charged with violating Pennsylvania abortion law by performing abortions after 24 weeks, operating a corrupt organization and other crimes. Gosnell was originally charged with seven counts of first degree murder.

Gosnell, 72, still faces five remaining murder charges and the possibility of the death penalty if convicted of any of the first-degree cases.

Judge Jeffery Minehart has not explained the reasoning behind today's rulling.

Former staffer Eileen O'Neill is also on trial. The 56-year-old Phoenixville woman is charged with practicing medicine without a license, and taking part in a corrupt organization. Six of the nine theft by deception charges she faced were dropped today as well because the prosecution didn't present any witnesses to support those charges.

The investigation into Gosnell's clinic began in February 2010 with agents from the Drug Enforcement Administration and the FBI who were conducting two raids on Gosnell's clinic in search of drug violations. Instead, they stumbled upon "deplorable and unsanitary" conditions, including blood on the floor and parts of aborted fetuses in jars. State regulators followed up with their own investigation, shutting down the Women's Medical Society clinic at 3801 Lancaster Avenue in West Philadelphia and suspended Gosnell'slicense.

The case then went to a grand jury. Their nearly 300-page grand jury report released in January 2011 described Gosnell's clinic as a filthy, foul-smelling "house of horrors" that was overlooked by regulators.

Prosecutors said Gosnell made millions of dollars over three decades performing thousands of dangerous abortions, many of them illegal late-term procedures. The clinic had no trained nurses or medical staff other than Gosnell, a family physician not certified in obstetrics or gynecology, yet authorities say many administered anesthesia, painkillers and labor-inducing drugs.

The grand jury report stated furniture and blankets in Gosnell's clinic were stained with blood, instruments were not properly sterilized and disposable medical supplies were used repeatedly.

Bags, jars and bottles holding aborted fetuses were scattered throughout the building, which reeked of cat urine because of the animals allowed to roam freely.

State regulators ignored complaints about Gosnell and the 46 lawsuits filed against him and made just five annual inspections since the clinic opened in 1979, investigators said. Several state employees were fired and two agencies overhauled their regulations after the allegations.

Gosnell has always maintained his innocence. He pleaded not guilty and has remained held without bail since his arrest. Prosecutors are seeking the death penalty in the infant deaths.

Prosecutors estimated Gosnell ended hundreds of pregnancies by inducing labor and cutting the babies' spinal cords and caused scores of women to suffer infections and permanent internal injuries, but they said they couldn't prosecute more cases because he destroyed files.

Eight clinic workers including Gosnell's wife, a beautician accused of helping him perform illegal third-term abortions, have pleaded guilty to a variety of crimes. Three of Gosnell's staffers, including an unlicensed medical school graduate and a woman with a sixth-grade education, pleaded guilty to third-degree murder for their roles in the woman's overdose death or for cutting babies in the back of the neck to ensure their demise.

In an interview with the Philadelphia Daily News after the clinic was raided, Gosnell described himself as someone who wanted to serve the poor and minorities in the neighborhood where he grew up and raised his six children, who include a doctor and a college professor.

McMahon, disputes that any babies were born alive. He has suggested that the woman who died, Karnamaya Mongar, had undisclosed respiratory problems that could have caused fatal complications.

McMahon has accused officials of "a targeted, elitist and racist prosecution" and "a prosecutorial lynching" of his client, who is black, and of applying "Mayo Clinic" standards to Gosnell's inner-city, cash-only clinic. He said Gosnell performed as many as 1,000 abortions per year, and at least 16,000 over his long career, with a lower-than-average complication rate.

After about a week of jury selection, seven woman and five men were chosen along with six alternate jurors. The trial began March 18 and is expected to last about two months.

Gosnell's former employees have testified that they were just doing what their boss trained them to do and described long, chaotic days performing gruesome work for little more than minimum wage paid under the table. An assistant testified she snipped the spines of at least 10 babies at Gosnell's direction, sobbing as she recalled taking a cellphone photograph of one baby she thought could have survived, given his size and pinkish color.

Mongar's 24-year-old daughter testified about the labor-inducing drugs and painkillers her mother was given as she waited hours for Gosnell to arrive for the procedure. She said her mother was later taken to a hospital, only after firefighters struggled to cut bolts off a side door of the clinic, but she died the next day.

Prosecutors wrapped up their five-week case with a former worker at Gosnell's clinic who testified that she saw more than 10 babies breathing before they were killed. The defense was slated to begin presenting its case Monday but Gosnell's attorney told the judge he was sick and went to a hospital for tests.