OTTAWA -- The Conservative government that earlier this year killed the national gun registry now says placing serial numbers on long guns contributes to public safety by allowing police to trace them.

The Public Safety department says that, effective Dec. 1, long-delayed rules on gun markings will come into force.

The rationale for the move, says a government backgrounder, is "to contribute to public safety, by facilitating law enforcement investigations when the markings can be linked to information on the last legal owner of the firearm."

But unlike the original 2004 regulations that have been postponed three times by the Harper government, the rules taking effect this year will not be enforced on gun makers, there will be no compliance measures and no penalties for non-compliance by gun owners.

And since the government is destroying the existing registry and legislating that gun dealers no longer record the identity of gun buyers, the practical usefulness of tracing serial numbers on firearms may be limited.

The new regulations also eliminate specific Canadian markings that were originally part of the legislation, a move that the Montreal-based Coalition for Gun Control says puts Canada in breach of international firearms protocols.