The Norwegian Forensic Medicine Commission and Norwegian practice
The issue was also of concern to the Norwegian judicial authorities (Table 1) (22–25). Scientific journals frequently cited international studies and debates. There was considerable uncertainty. In 1907, the Norwegian Forensic Medicine Commission stated that the average duration of pregnancy was 280 days from the first day of the last menstrual period, or 270 days from the date of conception (23).
Table 1
Limits for pregnancies resulting in live birth. Official Norwegian recommendations, 1823–1932.
| Date | Lower limit | Upper limit |
|---|
| Circular from the Ministry of Justice and Police, 1823 (17)
Based on the Faculty of Medicine's opinion | The fetus is viable ('vitalis') when born after the 31st week | 40 weeks after conception
[…] certain legal systems, in order to accommodate rare observations, have set the longest possible duration of pregnancy at 43 weeks and 1 day |
| Circular from the Ministry of Justice and Police, 1850 (17)
Based on the Faculty of Medicine's statement | 31 weeks (unchanged from 1823) | Four weeks beyond term; […] where all circumstances point to a post-term birth, the Faculty does not deny that it may occur 4–5 weeks after the normal due date |
| Circular from the Ministry of Justice and Police, 1851 (17)
Based on the Faculty of Medicine's opinion | Lower limit 210 days (30 weeks), on the basis that a fetus under favourable circumstances may be considered capable of […] independent life […] experience appears to show that, in some very rare cases, children born a couple of weeks before the 30th week may continue to live independently | Not specified |
| Circular from the Ministry of Justice, 1894 (22)
Based on the Faculty of Medicine's statement | The Faculty [must] emphasise the possibility that a fetus born between the 26th and 30th week, under very favourable conditions, may continue to live | The longest pregnancy duration is considered by the Faculty to be 310 days |
| The Forensic Medical Commission, 1907 (23) | […] the birth of a full-term child may occur after a gestational period of as little as 240–245 days following conception. | |
| The Forensic Medical Commission, 1913 (24) | | Pregnancy may last 315 days after conception |
| The Forensic Medical Commission, 1914 (25) | A fully mature child: 240 days after conception | 320 days counted from conception |
| The Forensic Medical Commission's report, 1932 (Rt. 1932, p. 324) | Pregnancy is calculated from the date of conception. 'The assumed delivery of a full-term child is an average of 270 days (precisely 274 days).' It recommends 240–320 days, as in 1914, 'essentially in agreement with circumstances in other countries'. |
The Commission commented in its 1907 report that determining whether a child was full term involved considerable uncertainty. 'For experts, it is among the more difficult questions to determine with certainty whether a child is full term or not. There are, in fact, no reliable signs by which it can be established whether a child is born one month prematurely or not. Weight and especially fetal length are among the best indicators' (23).
In 1914, the Commission revisited the issue (Figure 1). While maternity could virtually always be established medically, there was no capability to produce corresponding medical proof of paternity, and the legal evidence of paternity exclusion 'rests on a fact of natural science' (25). Given the variability in possible pregnancy duration and the uncertainty of neonatal indicators, the Commission recommended abandoning the need to prove paternity. In order to secure financial support for mother and child, it instead proposed replacing proof of paternity with proof of cohabitation, i.e. evidence of sexual intercourse between the man and woman during the possible period of conception. In some cases, under the 1892 law, several men were required to pay child maintenance as putative fathers of the same child. However, the cohabitation approach became a historical interlude.
Public interest in the presentation of evidence in paternity cases is reflected in the numerous cases reported in Norsk Retstidende throughout the 20th century. Establishing paternity could entail a considerable amount of legal work, and cases involving up to 50 witnesses have been reported (Rt. 1950, p. 537).
The core issue in these cases was whether the mother had had sexual intercourse with the alleged father at a time that could have resulted in the birth of the child. In 1914, the Norwegian Forensic Medical Commission set the lower limit for pregnancy duration in a full-term birth at 240 days after conception. A child could survive after a shorter gestational period but would not present as a full-term infant; however, such signs were difficult to determine. The upper limit was set at 320 days after conception. The lower and upper limits were thus 35 weeks and 5 days to 47 weeks and 1 day from the first day of the last menstrual period. This statement from 1914 carried considerable weight and was cited in numerous judgments up to the 1970s.
Leading obstetricians were used as expert witnesses in paternity cases throughout much of the 20th century, in the same way that expert witnesses have been used since the early 1980s in cases involving birth injuries. In 1920, Professor Brandt stated in his role as expert witness that 'these outer limits [240–320 days after conception] are so rare that only a handful of cases have been reported in the entire world literature, and I personally have never observed anything similar. Even time spans of 250–310 days are seldom encountered by obstetricians'. In one case, the court rejected the claim that a child had been born after 221–225 days, based on '[…] information concerning the child's stage of development at birth' (Rt. 1922, p. 55).
In his final statement as an expert witness in 1930, Brandt wrote: '[…] as I have repeatedly highlighted in several statements, if an unusually long gestational period is to be assumed, exceptionally strong evidence is required to rule out other opportunities for conception. It is for the court to decide whether such evidence exists […] The possibility is there; no one denies it, but it is unlikely' (Rt. 1930, p. 809).
Nevertheless, the time frame of 240–320 days remained applicable. A midwifery textbook from 1959 states: 'There is evidence that such short and such long gestational periods [240–320 days from the first day of the last menstrual period] can occur' (26). In contrast, the Norwegian Forensic Medicine Commission stated in 1914 that the relevant interval should be calculated from 'the time of conception'. It maintained this position when it revisited the issue in 1932. The framework was based on a series of assessments spanning nearly a century (Table 1).
In a 1967 judgment by the Norwegian Supreme Court, Professor Ernst Schjøtt-Rivers (1901–82), acting as an expert witness, argued that a child weighing just under 3600 grams, with a gestational age of 253 days from the alleged conception to birth, lay at the boundary between what was probable and what was improbable.
Referring to 'the usual theoretical outer limits of 240 and 320 days', the Supreme Court found (1–4) that the alleged father had 'had intercourse with the mother at a time when she could have conceived' (Rt. 1967, p. 1540). There was often doubt. Many judgments were delivered under dissent, and case reports from the 1960s frequently contained formulations such as 'a distinctly borderline case between the probable and the improbable' (Rt. 1968, p. 231), 'I concur, albeit with reservations' (Rt. 1968, p. 607), etc.
In a 1968 Supreme Court judgment, a man was found by a 3–2 majority to be the father of a full-term child born 306 days after conception (clinically 45 weeks + 1 day) (Rt. 1968, p. 442). Once again, the expert Schjøtt-Rivers considered that a gestational period exceeding 300 days after conception was unlikely. He further noted that the child's size and weight indicated that it had probably been born at term. Once again, the court adhered to 'the outer limits established in this country for pregnancy duration in cases of full-term birth, namely 240 to 320 days'. It was argued, and taken into account in the ruling, that an individual case could not always be decided 'on the basis of gestational age alone.'
However, the divergence between forensic medicine and clinical practice continued to emerge. In 1968, Schjøtt-Rivers stated 'I have always regarded these 240 days as a purely theoretical possibility, and there are no observed cases that can be accepted. It is assumed that reports of such short gestational periods resulting in full-term births are erroneous observations' (Rt. 1968, p. 231).
The annotated edition of the Norwegian Children Act rather dryly notes 'We are dealing with an extensive body of case law which is far from consistent in all details'. All the judgments illustrate the importance of an overall assessment (27). Before the era of DNA testing, paternity cases often involved considerable uncertainty. In 13 cases between 1950 and 1990, the Norwegian Supreme Court found the defendant to be the father by a 3–2 majority (28).