In 1988, radiocarbon dating was performed on samples taken from the Turin Shroud. The results indicated that the linen was manufactured between 1260 and 1390 CE, placing it in the medieval period rather than the first century. On this basis, the Shroud cannot be identified as the burial cloth of Jesus of Nazareth. Some proponents of the Shroud’s authenticity argue that these findings undermine traditional Christian beliefs, including the crucifixion and resurrection, while others dispute the reliability of the tests. Debate over the interpretation of the results has continued since their publication.
Radiocarbon dating is one of the most reliable and widely used methods for dating organic materials. Its basic principle is that cosmic rays generate an unstable isotope of carbon, Carbon-14 (¹⁴C), in the upper atmosphere. This isotope combines with oxygen to form carbon dioxide and is absorbed by living organisms through respiration or digestion. While an organism is alive, it maintains the same ratio of Carbon-14 to Carbon-12 as the atmosphere. After death, Carbon-14 decays at a known rate and is no longer replenished, causing the ratio to decrease over time. By measuring this ratio, scientists can estimate when the organism died. The method is well understood, the decay rate of Carbon-14 is precisely known, and long-term variations in atmospheric Carbon-14 have been carefully calibrated using tree-ring data.
In an attempt to challenge the radiocarbon results, chemist Raymond Rogers proposed an alternative dating argument based on chemical analysis, particularly the reported absence of vanillin in lignin fibers from the Shroud. Rogers argued that such a loss would imply a much greater age than that indicated by carbon dating. Critics, however, have noted that vanillin depletion can occur through several known processes, including heat exposure and chemical degradation. Given the Shroud’s documented history—including fires and environmental exposure—the absence of vanillin does not require an ancient date. Rogers’s argument therefore rests too heavily on a single indicator while neglecting plausible alternative explanations.
Various contamination hypotheses have also been proposed to explain the medieval radiocarbon dates. These include claims that linen can yield artificially young dates, that the cloth was contaminated by dirt or bacteria, that the samples came from a medieval repair, or that the Shroud’s turbulent history altered it chemically. These explanations frequently conflict with one another and are largely speculative. Crucially, no controlled studies using materials comparable to the Shroud have demonstrated that such contamination could shift a radiocarbon date by more than a millennium without leaving obvious physical evidence.
In 1983, Dr. Leoncio Garza-Valdes suggested that an invisible bacterial coating on the cloth might have distorted the radiocarbon results. Although bacteria were identified on the Shroud, this hypothesis was not supported by detailed, peer-reviewed publications. Experienced radiocarbon specialists have pointed out that any coating sufficient to alter the date by several centuries would have to be substantial and detectable. Moreover, the Shroud samples were carefully cleaned prior to testing.
Claims that contamination invalidated the medieval date have therefore been widely rejected. To produce a shift of approximately 1,300 years, contamination would need to constitute an unrealistically large proportion of the tested material. The samples were cleaned of debris and soot, and experimental work on linen exposed to heat and smoke comparable to the Shroud’s 1532 fire shows no such dramatic effect on radiocarbon dating. Two independent laboratories, using different subsamples and control materials of known age, obtained consistent results.
The fire of 1532 has also been ruled out as a cause of misleading results. The areas sampled for radiocarbon testing were cleaned of contaminants, and the control samples were dated accurately, demonstrating the reliability of the method. All three laboratories concluded that the flax used to make the Shroud died between 1260 and 1390 CE.
Suggestions that steam or water used to extinguish the fire altered the Carbon-14 content are unsupported. If radiocarbon dating were that easily disrupted, it would be unusable for archaeological materials, which is demonstrably not the case.
Even Ian Wilson, a leading advocate of the Shroud’s authenticity, has rejected claims that the samples were taken from a medieval rewoven patch or that the tested material did not originate from the Shroud. Textile analyses show that the samples are consistent with the rest of the cloth. Allegations that the samples were substituted at the last moment rely on speculation rather than evidence.
The theory advanced by Holger Kersten and Elmar Gruber—that the tested samples were not from the Shroud and that the Vatican orchestrated a hoax—has been widely discredited. The Vatican continues to treat the Shroud as a significant relic and publicly displays it, which is inconsistent with claims of deliberate deception. Moreover, there is no clear motive for falsifying the radiocarbon results, as the Shroud’s unusual characteristics do not require a supernatural explanation, nor do they compel identification with Jesus.
Some proponents argue that the tested area had been heavily handled or exposed to incense and candle smoke. However, it is generally acknowledged that contamination on the order of roughly 60% would be required to make the cloth appear more than a thousand years younger than its true age. Such extensive contamination would be detectable, even if some microorganisms are transparent.
Finally, appeals to multiple “coincidences” or alleged anomalies—such as claims about bacterial coatings, the medieval dating coinciding with a bishop’s statement, or interpretations of bloodstains and hair appearance—do not constitute evidence against the radiocarbon results. Rather, they rely on cumulative speculation. Scientific conclusions are based on controlled measurement and reproducibility, not on the number of unusual features attributed to an object.
As the official report on the radiocarbon testing makes clear, the sample was taken deliberately and with expert oversight from the main body of the Shroud, away from patches and damaged areas. The consistency of results across three independent laboratories, combined with the accurate dating of control samples, strongly supports the conclusion that the Turin Shroud is a medieval artifact. To say otherwise is to suggest a miracle equal to if not bigger than the alleged miracle of the image.
APPENDIX: CARBON DATING
The sample dates (in years before present (bp) with
likely error) from each laboratory were as follows:
Sample 1: Arizona (AA-3367): 591±30 bp, 690±35 bp, 606±41 bp and 701±33 bp.
Sample 1: Oxford (Ox-2575): 795±65 bp, 730±45 bp and 745±55 bp.
Sample 1: Zürich (ETH-2883): 733±61 bp, 722±56 bp, 635±57 bp, 639±45 bp and
679±51 bp
Sample 2: Arizona (AA-3368): 922±48 bp, 986±56 bp, 829±50 bp, 996±38 bp and
894±37 bp
Sample 2: Oxford (Ox-2574): 980±55 bp, 915±55 bp and 925±45 bp
Sample 2: Zürich (ETH-3884): 890±59 bp, 1,036±63 bp, 923±47 bp, 980±50 bp and
904±46 bp
Sample 3: Arizona (AA-3369): 1,838±47 bp, 2,041±43 bp, 1,960±55 bp, 1,983±37 bp
and 2,137±46 bp
Sample 3: Oxford (Ox-2576): 1,955±70 bp, 1,975±55 bp and 1,990±50 bp
Sample 3: Zürich (ETH-3885): 1,984±50 bp, 1,886±48 bp and 1,954±50 bp
Sample 4: Arizona (AA-3370): 724±42 bp, 778±88 bp, 764±45 bp, 602±38 bp and
825±44 bp
Sample 4: Oxford (Ox-2589): 785±50 bp, 710±40 bp and 790±45 bp
Sample 4: Zürich (ETH-3882): 739±63 bp, 676±60 bp, 760±66 bp, 646±49 bp and
660±46 bp
This is an unprecedented number of samples, with one set from the Shroud and three control samples: the laboratories were not told which sample came from the Shroud and which from the control objects. Those from each sample are consistent, so they can be combined into means. Sample 1 therefore has a mean radiocarbon date of 691±31 bp, which calibrates to 1262-1312, 1353-1384 CE at 2σ (95% confidence); sample 2 has a mean of 937±16, which calibrates to 1026-1160 CE at 2σ; sample 3 has a mean of 1,964±20, with a calibration of 9 BCE – 78 CE at 2σ; and sample 4 has a mean of 724±20, with a calibrated range of 1263-1283 CE at 2σ.
What do these dates mean? Sample 1 was from the Shroud, sample 2 from linen from a Nubian tomb of the eleventh to twelfth centuries CE, sample 3 was linen from a mummy of the early second century CE and sample 4 was from threads removed from the cope of St Louis d’Anjou dated to 1290-1310 CE. There is therefore no question that the Shroud is not medieval; we can be 95% confident that the cloth was manufactured between 1262 and 1384 CE.
BOOKS CONSULTED
Ante-Nicene Christian Library, Roberts and Donaldson, T&T Clark, Edinburgh, 1870
Biblical Exegesis and Church Doctrine, Raymond E Brown, Paulist Press, New York,
1985
Free Inquiry, Spring 1998, Vol 18, No 2, Article by Joe Nickell, Council for
Secular Humanism, Amherst New York
From Fasting Saints to Anorexic Girls, Walter Vandereycken and Ron van Deth,
Athlone Press, London, 1996
Holy Faces, Secret Places, Ian Wilson, Corgi, London, 1992
Inquest on the Shroud of Turin, Joe Nickell, Prometheus Books, Buffalo, NY, 1987
Jesus Lived in India, Holger Kersten, Element, Dorset, 1994
Looking for a Miracle, Joe Nickell, Prometheus Books, New York, 1993
Miracles, Ronald A Knox, Catholic Truth Society, London, 1937
Sceptical Inquirer 9/10 2001 Vol 25, No 5, Article by Joe Nickell, CSIOCP,
Amherst New York
Relics, The Society for Irish Church Missions, Bachelor’s Walk, Dublin
The Blood and The Shroud, Ian Wilson, Orion, London, 1999
The Book of Miracles, Stuart Gordon, Headline, London, 1996
The Divine Deception, Keith Laidler, Headline, London, 2000
The DNA of God?, Leoncio A Garza-Valdes, Doubleday, 1999
The Holy Shroud and Four Visions, Rev Patrick O Connell and Rev Charles Carty,
TAN, Illinois, 1974
The Holy Shroud and the Visions of Maria Valtorta, Msgr Vincenzo Celli, Kolbe
Publications Inc., Sheerbrooke, California, 1994
The Image on the Shroud, Nello Ballosino, St Paul’s, London, 1998
The Jesus Conspiracy, Holger Kersten amd Elmar R Gruber, Element, Dorset, 1995
The Jesus Relics, From the Holy Grail to the Turin Shroud, Joe Nickell, The
History Press, Gloucestershire, 2008
The Second Messiah, Christopher Knight and Robert Lomas, Arrow, London, 1998
The Skeptic’s Guide to the Paranormal, Lynne Kelly, Allen & Unwin, Australia,
2004
The Shroud, The 2000 Year Old Mystery Solved, Ian Wilson, Bantam Press, London,
2010
The Turin Shroud is Genuine, Rodney Hoare, Souvenir Press, London, 1998
The Turin Shroud, Ian Wilson, Penguin Books, Middlesex, 1979
The Unauthorized Version, Robin Lane Fox, Penguin, Middlesex, 1992
Turin Shroud, Lynn Picknett and Clive Prince, BCA, London, 1994
Verdict on the Shroud, Kenneth E Stevenson and Gary R Habermas, Servant
Publications, Ann Arbour, Michigan, 1981