The group called for age-based restrictions on music sales, similar to existing systems that prevent underaged consumers from obtaining inappropriate movies and video games. They also called for controls that would prevent radio and television stations from airing violent content before 9 p.m.

"We have listened to the research, and cigarette packs now carry large and graphic warnings about the dangers of smoking," Prof. Peter Jaffe of the University of Western Ontario told a news conference.

"Where are the warnings on the many forms of media violence readily accessible by children? Tiny ratings stickers just don't cut it any more."

Jaffe cited decades of "clear and compelling" evidence that he said illustrates the long-lasting negative impact of violent media on children, and said medical and mental-health experts agree it has become a very serious problem.

"Viewing entertainment violence can lead to increases in aggressive attitudes, values and behaviour, particularly in children," he said.

"We've been exposed to more and more [violence] so that we've gotten desensitized. We no longer get outraged because we've seen it all."

The teachers, trustees and parent groups said it's not just video images on television and the Internet that are exposing children to violent behaviour.

"Music has escaped the need for classification, despite the fact that the music industry has gone the way of film, television and video games in producing explicitly violent, sexual material," said Rhonda Kimberley-Young, president of the Ontario Secondary School Teachers Federation. "We believe that some of this material is damaging to children and youth and should be restricted to those over the age of 18."

In addition to the music classification system and changes to the Broadcasting Act, the coalition also called on the federal government to amend the Criminal Code to add women to the list of groups that are protected under the section prohibiting public incitement of hatred.

"We believe that leaving girls and women off the list compromises their safety," Kimberley-Young said.

"Recommendations to add 'sex' or 'gender' to the groups protected by the public incitement of hatred law have been on the table for at least 20 years now."

The group showed a video depicting huge, bulked-up professional wrestlers attacking women and ripping off their clothes as an example of the type of violence against women that kids can routinely see on television -- images Jaffe said he hoped would not be allowed if the law were changed.

© The Vancouver Province 2007