Sunday, April 7, 2019
A DNA Test may not automatically overcome a Brick Wall situation
The term "brick wall" as used in the genealogical sense refers to an end-of-line situation where the next generation ancestor or even some other relative cannot be easily found. Of course, this could be the researcher's parent or parents but in most cases, it is one or more of a more distant ancestor or relative. As a side note, I think the term is very inappropriate as it implies that some external force is preventing you from finding a particular person. There is a huge body of writings and videos on the subject of overcoming genealogical brick walls, See "The Ultimate Genealogical Brick Wall Buster" for example.
Lately, with the increased interest in genealogical DNA testing, there are numerous examples of articles, advertisements, and other media mentions about finding the "long lost ancestor." Most of these deal with reunions between members of close biological families, i.e. finding parents or siblings. However, there is an undercurrent of articles about solving complex genealogical mysteries, i.e. brick walls, using DNA tests.
First of all, DNA testing is not absolute proof of a relationship between two individuals. When the individuals tested are extremely closely related, such as a parent and a child, the results of a DNA test do approach certainty but with each generation of removal from the test subject, the uncertainty of the accuracy of the test decreases. The use of DNA tests to establish paternity date back to 1988. Before that, blood tests were used that could only suggest a relationship or rule out one altogether. The first use of DNA testing in a criminal case occurred back in 1986 in England. After many law cases over the succeeding years, DNA testing in criminal cases has become routine. The first case that allowed DNA to be used for evidence was a New York criminal case, People v. Wesley, 140 Misc.2d 306 (1988). However, the case was appealed and finally, the use of DNA testing upheld in the New York Court of Appeals, see People v. Wesley, 83 N.Y. 2d 417 (1994). By that time, I had been practicing law for about 19 years.
During the years following that first lawsuit, the use of DNA testing for evidentiary purposes expanded slowly in the legal community. Almost every case where it was attempted to be used and admitted by the courts ended up in an appeal. It was years before DNA testing was allowed routinely, but it is still objected to based on the method of collection and other evidentiary custodial grounds.
I think there is way too much science being talked about in conjunction with genealogical DNA testing and not nearly enough about the methodology and the accuracy of the particular procedures used in taking the tests. Automatically assuming that the results of any particular DNA test are accurate is not only bad science it is poor genealogical methodology. Before you start to get upset, think about how the tests are administered. The procedures and the possibility of contamination are left entirely up to people with absolutely no experience in conducting such a test: the people who buy the kit from the supplier and sometimes off of a store shelf.
If any of the multitudes of DNA tests out there were used in a law case where I was representing a party, I would have little or no trouble in getting the test disqualified.
Then how do law enforcement agencies use a DNA test to solve cold cases? They don't they use the DNA test to suggest suspects and then obtain a properly conducted DNA test to establish the evidence that is taken to court. The argument is whether or not the DNA information from a third party supplier such as one of the genealogical DNA testing companies can be used to establish probable cause for arrest and the acquisition of DNA from a suspect. The case is not proved until the suspect's DNA matches some DNA obtained from the crime scene.
What does this have to with genealogy? First of all, as I have already mentioned, the DNA tests are very popular and are being advertised as a solution to genealogical mysteries, i.e. brick walls. One basic part of the DNA testing that should be emphasized is that they are a mere novelty without careful genealogical research in a family tree that is supported by the results from the DNA tests. For example, it is not very helpful to find out that someone is your 3rd or 4th cousin various times removed unless there is some way to figure out how you are related. In this regard, MyHeritage's The Theory of Family Relativity is a giant leap forward in integrating DNA tests with family tree information and sources. But unless you are already familiar with your own ancestry and have a well-sourced family tree on the MyHeritage.com website, you will still be unable to analyze and use the information.
Every generation back in time more than doubles the number of potential ancestors you have due to people with multiple marriages and etc. Stories of DNA solving difficult relationship issues with relatively remote ancestral relationships are almost always the product of extensive paper research to identify the people who might be candidates for a match to show a researched relationship to a common ancestor.
So taking a DNA test without the support of a family tree, may or may not help you find a connection in your first two or three generations. But without a sourced family tree once you get back past three or four generations, a DNA test is only useful after intensive genealogical research and an understanding of how the DNA may help to find the common ancestor.