The B.C. Court of Appeal has allowed an "extraordinary" time extension to enable a man accused of sexually abusing his children to appeal a family case "more than three years out of time."

The decision comes after the court learned that the credentials of a so-called expert witness who testified in the major child abuse case were called into question by the accused father's legal team.

A release on the B.C. Court of Appeal website today said the decision to grant an application was granted.

"Although granting an extension of time in the face of a three-year delay is extraordinary, this case is extraordinary and the interests of justice overwhelmingly favour it. There is evidence that an expert tendered by the mother at trial to prove the abuse was a fraud. The "expert" not only may have lacked bona fide credentials and experience, but her opinion relied on a debunked and inadmissible scientific theory. This evidence permeates the judgment, including the sexual abuse findings," wrote Madam Justice Elizabeth Bennett.

Today's ruling means the legal team for the man — known only as B.G.— can now prepare an appeal of the original family case which heard evidence from experts that led to him being labelled a child abuser.

CBC News learned that the case involved a woman whose professional views have been labelled "bizarre."

Claire R. Reeves, 74, who calls herself a doctor of psychology, holds controversial views on the Catholic church, mind control and transgender individuals.

The case revolved around the mother's claims that the province's Ministry of Children and Family Development had ignored her suspicions that her husband, B.G., was sexually abusing their children.

Ministry workers had labelled the mother -- known as J.P.-- mentally unstable, and awarded unsupervised access to the father.

The family court judge reviewing the case, Justice Paul Walker, ultimately ruled B.G. had indeed molested the children, based on months of evidence and the testimony of several expert witnesses — including Claire R. Reeves.

B.G. — the father — was never charged criminally. 

With files from Eric Rankin