I am looking for information on criminal cases and convictions for the criminal act under section 171-Householder permitting sexual activity of the criminal code in Canada. Where can I find that information?

Have you tried the following two types of searches? There might be some case law available on some of the sites that come up.

171-Householder permitting sexual activity of the criminal code in Canada. - Google Search

171 Householder permitting sexual activity of the criminal code in Canada Case Law - Google Search