Court documents released Monday have shed some light on why convicted sex offender Martin Tremblay has been allowed to live unmonitored in B.C. for years.

CTV News learned last month that Tremblay was living at a Richmond, B.C., house where 17-year-old Martha Hernandez was found dead from a mix of drugs and alcohol.

Tremblay was convicted of sexual assault in 2003 for drugging and sexually assaulting teenage girls.

After his arrest in 2002, Tremblay was originally charged with 18 criminal offences involving aboriginal girls between the ages of 13 and 15. Counts of administering a noxious substance and sexual assault were just some of the charges.

But for some reason, Crown counsel dropped 13 of those charges. Tremblay pled guilty to five counts, and used his rocky relationship with his wife to excuse his behaviour.

Tremblay's former wife has told CTV News that she ended the marriage when she observed some troubling tendencies, including a predilection for socializing with under-aged girls.

On Monday, the B.C. Supreme Court released a transcript of the judge's reasons for Tremblay's 2003 sentence -- he could have been in prison for 10 years, but the judge only put him away for three and a half.

The judge depended on a psychiatric assessment that suggested Tremblay wasn't a pedophile, but rather suffered from what the doctor called an "adjustment disorder."

Advocates with the group Justice for Girls say that prosecutor Kathryn Ford should have asked for conditions to keep Tremblay away from girls under the age of 18.

That didn't happen, and it appears that the Crown didn't pursue having Tremblay registered as a sex offender.

"The criminal justice system is not protecting those girls. It's failing them," Annabel Webb of Justice for Girls told CTV News.

"My question to the Crown is, what could they have done to get him a sentence that would have allowed police to monitor him in an ongoing way?"

CTV News has tried to speak with Crown counsel several times over the past two weeks about why they chose not to ask for Tremblay to be monitored after his release from jail.

Representatives of the Crown have said that while they recall the case, they need more time to refresh their memories.

With a report from CTV British Columbia's Lisa Rossington