Corroborating Evidence

Corroborating evidence (in "corroboration") is evidence that tends to support a proposition that is already supported by some initial evidence, therefore confirming the proposition. For example, W, a witness, testifies that she saw X drive his automobile into a green car. Meanwhile Y, another witness, testifies that when he examined X's car, later that day, he noticed green paint on its fender. Or there can be corroborating evidence related to a certain source, such as what makes an author think a certain way due to the evidence that was supplied by witnesses or objects.

For more information on this type of reasoning, see: Casuistry.

Another type of corroborating evidence comes from using the Baconian method, i.e. the method of agreement, method of difference, and method of concomitant variations.

These methods are followed in experimental design. They were codified by Francis Bacon, and developed further by John Stuart Mill and consist of controlling several variables, in turn, to establish which variables are causally connected. These principles are widely used intuitively in various kinds of proofs, demonstrations and investigations, in addition to being fundamental to experimental design.

In law, corroboration refers to the requirement in some jurisdictions, such as in Scotland, that any evidence adduced be backed up by at least one other source (see Corroboration in Scots law).

Corroboration is not needed in certain instances. For example, there are certain statutory exceptions. In the Education (Scotland) Act, it is only necessary to produce a register as proof of lack of attendance. No further evidence is needed.