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How to Evaluate Genealogical Evidence

How To Evaluate Genealogical Evidence

To be successful in genealogical research, one must master the process of testing information for accuracy. Researchers may use dozens of sources as they strive to gather evidence in support of a relationship. However, not every source or piece of evidence is always reliable. Some information found during the course of research is more likely to be true than other information. Statements made by family members cannot always be taken at face value for a variety of reasons. Official records can also contain a variety of errors. The key to being successful and accurate is the ability to identify and understand the many aspects of each record that must be evaluated for accuracy.

Traditionalists have insisted that sources be classified as either primary or secondary. Experience has shown that while the definition of both types of records may be straightforward to legal experts, professional genealogists, and scholars, it can be difficult to decide what is a primary source and what is a secondary source. We have multiple issues here: the nature of the records themselves (how they were created), and the origin of the information in the record. A good example of how confusing the situation can get involves a death certificate. Most death certificates were created at or near the time of death, and that definition often is associated with the term primary record. However, much of the information on that certificate pertains to events that happened years before the event of death, such as the birth date and birth place of the deceased, and the parents' names, making the record secondary in regards to these facts.

Due to the difficulties in comprehending differences between primary and secondary sources, some genealogists have called for eliminating these "artificial" terms. Others feel we should continue to have the categories but put more emphasis on the art of evaluating regardless of the category. For each piece of genealogical evidence we discover, there are at least six separate factors to weigh when evaluating our findings:

1. Origin Of Information. The information contained in a record that should be considered as primary or secondary. Most records contain elements indicative of both primary and secondary information. An example of this would be census data. The 1920 census identifies relationships at the time the census was taken. That would be considered primary data. However, the age and birthplace of the adults in the same census are only secondary, since, by definition, primary information is that which was recorded at or near the time of the event or situation that happened. Secondary information is information that was recorded much later than the event it describes, and/or by someone not closely associated with the actual event or was not in a position to know firsthand.

2. Nature Of Records. The nature of the record has no bearing on the information. A compilation of marriages, taken from original county records, still presents primary information. However, the nature of the source allows for the possibility of errors. This is where a consideration of the categories and formats of records can be useful in the evaluation process.

Genealogical records comprise two categories--original and compiled records. Original records were created to record certain events. They were generally written close in time to the events they record and are usually the earliest record of such events. A baptismal record is an original record, as are obituaries, military pension papers, business account books, city directories, and most newspaper articles. In all of these examples, the information was written directly into the record by someone who was in a position to have accurate knowledge of the information being recorded.

Compiled records or, as some call them, records of a previous search, represent a gathering of information from one or more additional sources. These can be original or compiled records or a combination of both. The important consideration here is that someone interpreted the information found in other sources. Examples of this would include family histories, biographies, and local histories of a city, county, organization, or township. Often they are published books, although this is not a requirement, especially with new formats such as the Internet.

Genealogists often use other records in their research which do not directly add names to their files. In compiling a list of sources, many often ignore recording sources such as gazetteers, dictionaries, and how-to books. They might be listed under reference tools as sources if they are listed. Such records also conveniently divide into two categories: background information and finding aids.

3. Kinds Of Formats. The formats of the records also makes a significant difference when evaluating the evidence found therein. Recording errors can appear in any source, but the nature of the errors changes with the format. The actual document, either an original or a compiled record, is often available to the researcher. Virtually as good as the actual document is a photographic copy, including microfilm, microfiche, or photocopy. In either of these cases, the researcher is viewing the record as it was first made, and any errors are the fault of the person who made the record. Copy errors may be introduced if the document was transcribed, extracted, or abstracted. Researchers must always take this into consideration when weighing the evdience either for or against the accuracy of an individual record. If such copies are a printed copy, the genealogist must account for possible copyist and typographical errors. In a manuscript copy, there may still be copyist errors, but there is now the possibility of misreading the handwriting.

4. Directness Of Evidence. Evidence will consist of statements of fact made in a record or the interpretation of the facts in a record. A direct statement specifically states a fact, such as the date of marriage, or death. An indirect statement, also called circumstantial evidence, implies a fact or event. A marriage record is direct evidence that a person was born, but only indirect evidence of the time of birth because the person may have been born 20 or more years before the marriage took place. Researchers prefer direct evidence because indirect evidence is open to interpretation.

5. Consistency Of Facts. Every record includes several facts or alleged facts. The researcher must judge these facts in conjunction with other facts in the same record or in similiar records dealing with the same fact or event. Consistency, or lack thereof, determines whether the facts agree with the known, proved, or accepted facts, or if they disagree with what has been known up until the present time. If a birth record indicates a child was born a year after the known death of the father listed on the birth record, a serious disagreement exists which must be resolved before that record can be accepted as proof of the child's paternity.

6. Could The Event Have Occurred. Original records generally document specific events in the life of a person. Compiled records also list events, along with other facts about individuals. Part of this evaluation process requires the researcher consider whether the events, as shown in the records, could have occurred in the setting as described by the facts. Some events, such as joining the military at the age of ten or twelve, being born on the father's birthday, having a probate inventory reveal a considerably larger personal estate than recent tax lists or census records justified are less credible than others. Such events are certainly possible but unlikely. There is a continuum of probability ranging from very likely, to highly unreasonable, to impossible for most situations. This continuum can vary with different cultures and time periods.

7. Evaluation And Proof. Each record must be evaluated individually, based on these criteria as evidence, but proof is the accumulation of acceptable evidence. The researcher must act as the ultimate judge. The researcher is responsible for determining if the accumulated evidence represents clear and convincing proof. In evaluating evidence, it is crucial for all researchers to realize that original records are not inherently better or worse, than compiled records. However, they do need to be evaluated differently. The same is true with the information contained in the record. Primary information is not necessarily more correct than secondary information. Every genealogist knows of cases where clerks made mistakes in recording events and relationships than the originals that they may be based on.

The evaluator must also consider the format, evidence, facts, and events for each record, keeping in mind that each of these aspects must be evaluated differently. Using descriptors (such as original or compiled records, primary or secondary information, actual or copied records, direct or indirect evidence, agreeable facts, and likely events) provide a useful approach when tanalyzing the different ways in which each record must be evaluated.


American Society Of Genealogists. Genealogical Research: Methods And Sources. 2v. Revised Edition. Washington, DC: American Society Of Genealogists, c1980. Genealogy Ref. 929.1 Gen.

Greenwood, Val D. Researchers Guide To American Genealogy. 2nd Edition. Baltimore, MD: Genealogical Publishing Company, c1990. Genealogy Ref. 929.1 Gre.

Harland, Derek. Genealogical Research Standards. Salt Lake City, UT: Bookcraft Inc., c1963. Genealogy Ref. 929.1 Har.

Meyerrink, Kory L. Evaluation Of Evidence. Ancestry Newsletter, v.10, no.6, November-December 1992. Salt Lake City, UT: Ancestry Publishing.

Stevenson, Noel C. Genealogical Evidence: A Guide To The Standard Of Proof Relating To Pedigrees, Ancestry, Heirship, And Family History. Laguna Hills, CA: Aegean Park Press, c1979. Genealogy Ref. 929.1 Ste.

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Szucs, Loretto Dennis and Sandra Hargreaves Luebking. The Source: A Guidebook Of American Genealogy. Revised Edition. Salt Lake City, UT: Ancestry Inc., c1997. Genealogy Ref. 929.1 Szu.

Wright, Raymond S. The Genealogists Handbook: Modern Methods For Researching Family History. Chicago, IL: American Library Association, c1995. Genealogy Ref. 929.1 Wri.

Compiled by Bryan L. Mulcahy, Reference Librarian, Fort Myers-Lee County Library, 10/12/98.

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