A Hsinchu Science Park engineer who was indicted on offenses against the family for having a child with his mistress while he was married, was recently exonerated after a calculation of the last ovulation date of the mother proved that he did not cheat on his former spouse before their divorce was finalized.
According to the verdict issued recently by the Hsinchu District Court, the defendant, surnamed Kuo (郭), had divorced his former spouse, surnamed Chen (陳), on Mar. 4, 2009, and had offered a monthly maintenance of NT$6,000 for their children.
After Kuo failed to make good on his promise, Chen filed a civil lawsuit against him in July 2010 with the Taichung District Court, demanding that he pay the maintenance.
Two months later, Chen applied for a copy of Kuo’s household registration in an effort to gather information on his listed properties and income for the trial, only to discover that an unknown child was registered under her former husband’s residency.
Chen learned that the child — a girl — had been fathered by Kuo with the woman she believed to be his mistress, surnamed Lai (賴), and was born on Nov. 13, 2009.
With a rough calculation of Lai’s likely conception date pointing to the time before her divorce of Kuo had become official, Chen then pressed charges against her former husband with the Hsinchu District Prosecutors’ Office for offenses against the family.
Prosecutors accordingly indicted Kuo, saying that the baby was concrete evidence that he and Lai had been having an affair.
Lai, who later married Kuo, maintained in court that she and Kuo only started dating on her birthday on Mar. 6, 2009, when he proposed to her and had sexual intercourse with her, and that they had not had sex while Kuo was still married to Chen.
The court ruling said that Kuo and Lai claimed to have got married after the latter learned of her pregnancy.
However, both prosecutors and the district court dismissed their testimony, citing the record of one of Lai’s three abortions between 2007 and 2008 in which Kuo was listed as the emergency contact.
Lai’s medical records were pulled by the district court after Kuo, despite having known Lai since 2006 when he was transferred to the factory where she was working, vehemently denied having an extramarital affair with Lai.
Lai also maintained that she only listed Kuo as the emergency contact because she had no other acquaintances in Hsinchu.
Meanwhile, Kuo’s defense attorney, Yang Lung-yuan (楊隆源), questioned the accuracy of the estimated conception date for Lai that Chen and prosecutors calculated based on the general medical theory that the due date of an expectant mother is 280 days from the first day of her last period.
Yang said that as there was a so-called “safe period” after the conclusion of the menstrual period, the actual duration of the pregnancy of a mother-to-be should be 266 days, after having deducted the first 14 days — known as the follicular phase — in which the woman does not ovulate, from the 280-day gestation period.
“This, combined with the fact that Lai delivered the baby 14 days earlier than her originally calculated due date of Nov. 27, 2009, because of fetal malposition, means her real conception date should fall at about Mar. 6, 2009,” Yang said.
Also, if Lai’s last period before pregnancy started on Feb. 20, 2009, as she had claimed, the date of her next ovulation should therefore be 14 days later on Mar. 5, 2009, Yang said.
“You can get the date of around Nov. 27, 2009 — Lai’s original due date — if you add the actual gestation period of 266 days to the date of her possible last ovulation on Mar. 5, 2009,” Yang said.
In an attempt to accurately pinpoint Lai’s conception date, the court subsequently ordered the hospital where Lai underwent her prenatal examinations to ascertain the date.
Judging from the length of the fetus and the development of her skull as shown in ultrasound records, the hospital concluded that Lai’s conception date should be Mar. 5, 2009, one day after Kuo and Chen’s divorce.
The judge accordingly ruled Kuo not guilty based on the hospital’s conclusion.
Commenting on the case, Yang said: “Wining a case by resorting to an accurate calculation of one’s ovulatory period not only is something I did not expect, but is also extremely rare in legal history.”