What is the test for “palpable and overriding error”?

Following Housen, Waxman provides a useful summary of what is meant by “palpable and overriding error” in paras. 296-297: The "palpable and overriding" standard addresses both the nature of the factual error and its impact on the result. A "palpable" error is one that is obvious, plain to see or clear: Housen at 246. Examples of "palpable" factual errors include findings made in the complete absence of evidence, findings made in conflict with accepted evidence, findings based on a misapprehension of evidence and findings of fact drawn from primary facts that are the result of speculation rather than inference. An "overriding" error is an error that is sufficiently significant to vitiate the challenged finding of fact. Where the challenged finding of fact is based on a constellation of findings, the conclusion that one or more of those findings is founded on a "palpable" error does not automatically mean that the error is also "overriding". The appellant must demonstrate that the error goes to the root of the challenged finding of fact such that the fact cannot safely stand in the face of that error: Schwartz v. Canada, 1996 CanLII 217 (SCC), [1996] 1 S.C.R. 254 at 281.