Birth parents and adult adoptees in Ontario can now get information about one another under the province's Adoption Information Disclosure Act.

The legislation, which went into effect Monday, allows adoptees who are 18 or older to obtain copies of their original birth registration and adoption orders containing their original birth name and birth parents' names. Birth parents can also get details from those records if the adoptee is 19 or older.

The act, which amends the Child and Family Services Act as well as the Vital Statistics Act and was passed in 2005 in stages, allows both parties to protect their privacy by requesting a no-contact notice. That means a birth parent or adoptee must agree not to contact the person who registered the notice before details from records are disclosed.

"We're very excited," said Michael Grand, a University of Guelph psychology professor and spokesman for the Coalition for Open Adoption Records, an umbrella group endorsed by adoption groups including Parent Finders Canada, the Adoption Council of Canada and the Canadian Council of Natural Mothers.

But the act is being fought by opponents. In June, three adoptees and one birth parent represented by Toronto lawyer Clayton Ruby mounted a constitutional challenge to the legislation, arguing it's a serious breach of privacy.  

Grand said the coalition, which was granted intervener status in the case, has been told that presiding judge Edward Belobaba will make a decision on Wednesday.

Regardless of the outcome, one side will likely make an appeal at the Supreme Court of Canada, he said.

British Columbia, Alberta, and Newfoundland and Labrador have similar legislation, but those provinces included a disclosure veto that protects the identities of those who wish to remain anonymous.

Under the new act, Ontario is also providing a voluntary adoption disclosure registry, which allows birth parents and adopted adults to exchange contact information.