The Supreme Court of Canada in Ottawa on July 21, 2011. (ANDRE FORGET/QMI AGENCY)

OTTAWA — A man convicted of repeatedly beating and raping his stepdaughter — who is also his niece — while she was a young girl shouldn't walk free just because parts of her testimony three decades later were unreliable, the Supreme Court ruled Thursday.

The complainant testified as an adult about repeated physical and sexual abuse that took place in the early 1980s, when she was between the ages of 8 and 13.

The defendant, Harry Persaud Sanichar, is her father's brother. Sanichar married her mother following his brother's death. Her mother died in 1984 of acute alcohol poisoning.

According to court documents, Sanichar was accused of sexual touching, vaginal and anal intercourse as well as physical beatings that were described as "commonplace."

Sanichar was found guilty of all 12 counts of sexual abuse in June 2008.

The Ontario Court of Appeal allowed his appeal and ordered a new trial in part due to the absence of corroborating evidence and the fact that the complainant didn't remember every detail with the same degree of precision.

The Crown appealed to the Supreme Court.

Sanichar was sentenced to 3 1/2 years in prison, but has been free since March 2009 pending the outcome of the appeals.

He will now be going back to jail.