Sometimes the truth is stranger than fiction, or at least as strange as a TV movie. Just look at the case of Patricia Stallings. She was given life in prison after being found guilty of ki*lling her infant son, but she was later found not guilty thanks to the hard work of three medical investigators.
In the summer of 1989, Stallings took her three-month-old son Ryan to the emergency room of St. Louis’s Cardinal Glennon Children’s Hospital. This was the start of the story. The child was having trouble breathing, throwing up, and having stomach problems. The child’s symptoms pointed to being poisoned with ethylene glycol, which is found in antifreeze, according to the attending doctor, who is a toxicologist. This conclusion was reportedly supported by testing at a commercial lab. The child was put in a foster home after he got better, and Stallings and her husband David were able to see him on supervised visits. The baby got sick and died after a visit during which Stallings was briefly left alone with him.
She was then charged with first-degree mu*rder and held without bail. Both the commercial lab and the hospital lab found large amounts of ethylene glycol in the boy’s blood and traces of it in a bottle of milk Stallings fed her son during the visit. At the time, the evidence seemed strong. But Stallings had done a great experiment without even realizing it. She found out she was pregnant while she was in jail, and in February 1990, she gave birth to another son, David Stallings Jr. He was put in a foster home right away, but within two weeks, he started showing signs that were similar to Ryan’s. David was eventually told he had methylmalonic acidemia (MMA), a rare metabolic disorder. About 1 in 48,000 babies are born with MMA, a genetic disorder that affects how amino acids are used.
The symptoms are very similar to those of ethylene glycol poisoning. Even though new evidence showed that Stallings couldn’t have poisoned her second son, the Missouri state prosecutor’s office didn’t care and went ahead with her trial anyway. The court wouldn’t let the second child’s MMA diagnosis be used as proof. In January 1991, Patricia Stallings was found guilty of assault with a deadly weapon and given a life sentence. While Stallings was in trouble, William Sly, who is the head of the Department of Biochemistry and Molecular Biology at St. Louis University, and James Shoemaker, who is in charge of a metabolic screening lab at the university, became interested in her case after seeing it on TV. Shoemaker looked at Ryan’s blood on his own and didn’t find any ethylene glycol. He and Sly then called Piero Rinaldo, a metabolic disease expert at Yale University School of Medicine. Blood samples can be used to diagnose MMA in Rinaldo’s lab. Rinaldo looked at Ryan’s blood serum and found that it had a lot of methylmalonic acid.
This is a breakdown product of the branched-chain amino acids isoleucine and valine, and it builds up in MMA patients because the enzyme that should change it into the next product in the metabolic pathway doesn’t work right. He also says that the fact that the child’s blood and urine had huge amounts of ketones, which are another metabolic effect of the disease, is very telling. Similar to Shoemaker, he did not find any ethylene glycol in a sample of the baby’s blood or urine. It was impossible to test the bottle because it had mysteriously vanished. Rinaldo’s research led him to believe that Ryan had died from MMA, but how to explain the fact that two labs had found ethylene glycol in the boy’s blood? Could each of them be wrong?
Rinaldo says what he saw when he got the lab reports was “scary.” One lab said that Ryan Stallings’ blood had ethylene glycol in it, even though the analysis of the blood sample did not match their own profile for a sample that they knew had ethylene glycol in it. “This wasn’t just a matter of interpretation that wasn’t clear.” Rinaldo says, “The quality of their analysis was not good enough.” What about the second lab? The lab found something strange in Ryan’s blood, and Rinaldo says they “assumed it was ethylene glycol.” Rinaldo says that samples from the bottle didn’t show anything strange, but the lab said that there was evidence of ethylene glycol in those samples as well. Rinaldo told the prosecutor in the case, George McElroy, what he had found. McElroy then set up a press conference for the next day. He told reporters, “I no longer believe the lab data.” Once McElroy was sure that Ryan Stallings had died from MMA, he dropped all charges against Patricia Stallings on September 20, 1991.
