In 1989, Patty Stalling, a store clerk in St. Louis, rushed her infant son Ryan to the hospital. He was vomiting excessively and was having trouble breathing. Doctors ran tests and concluded that the child had been poisoned with antifreeze. He died in care four days later and Patty was arrested for first-degree murder.
While she was in jail awaiting trial, Patty gave birth to another son, David Jr., on February 17, 1990. He was placed in foster care, had barely been near his mother, but yet, in March, he developed similar symptoms as those that had killed his brother.
Putting the evidence together, a Doctor diagnosed David with methylmalonic acidemia (MMA), a genetic condition in which the body produces propionic acid, a compound that differs from ethylene glycol by one carbon atom and can easily mimic antifreeze poisoning.
With the correct treatments, David recovered but was still kept from his mother.
The Prosecution didn’t buy it. They were convinced that Stallings was a murderer. For them, the diagnosis was wrong, plain and simple. Adding to their case was the fact that Patty’s lawyers couldn’t produce more evidence of her innocence.
In May 1990, defense attorney Eric Rathbone managed to get copies of notes written by assistant prosecutor John S. Appelbaum that indicated that the doctor who pronounced Ryan dead had considered the possibility of an MMA diagnosis, but also that he had not tested Ryan for that.
After the case was featured on national television, biochemist William Sly agreed to test Ryan's blood and gave it to Dr. James Shoemaker, M.D., Ph.D., Director of the Metabolic Screening Lab at St Louis University.
Shoemaker immediately confirmed that Ryan had had MMA. Shoemaker asked the prosecutor for the methods that had been used to measure ethylene glycol in Ryan's blood, and McElroy supplied that information. When the method was used on blood from Ryan and DJ, it was seen that propionic acid, which is produced in methylmalonic acidemia, caused a result that careless observers might mistake for ethylene glycol.
Shoemaker then sent samples of propionate-spiked blood to several laboratories, who tested it with the same methods used in the Stallings case. Some of the laboratories came to the incorrect conclusion that the blood reflected ethylene glycol poisoning. Finally, Prosecutor McElroy was convinced that Ryan wasn’t poisoned.
By then Patty had been in prison for two years. She was finally released in 1991. She sued the hospital and laboratories that were involved in Ryan's care and reached an out-of-court settlement. Prosecutors later apologized to her. Still, in 1994, McElroy ran for reelection as Jefferson County prosecutor, and Stallings donated $10,000 to his opponent who won the election.
