The patient was pregnant with twins. One of them was one of those yucky babies with Down syndrome and (common for DS) a heart defect. The other was a healthy girl. The mother asked Dr. Matthew Kachina to do a "selective reduction" -- a nice way of saying, "Kill the yucky baby and leave the cute one."
He accidentally killed the standard baby, leaving the genetically "defective" baby untouched. The mother got the yucky baby snuffed and sued the doctor, who was involuntarily hospitalized and put on suicide watch.
If unborn babies are disposable, accidentally snuffing "the wrong one" is no bigger a deal than accidentally towing the junk Chevy to the wrecking yard when you were supposed to tow the junk Ford. If killing one of the babies was something worth getting suicidal about, why was it a good thing to try to kill the other one?
It reminds me of that exchange in Huckleberry Finn:
"We blowed out a cylinder-head."
"Good gracious! anybody hurt?"
"No'm. Killed a nigger."
"Well, it's lucky; because sometimes people do get hurt."
Now it's "retards" rather than "niggers" who aren't people. It's as if some people just have to have somebody they can dehumanize.