The Cheyenne Police Department will host a seminar on ''Why Teens Kill" on May 21 at the Cheyenne Civic Center, according to spokesman Officer Dan Long.

The seminar will be presented by Phil Chalmers, who Long identifies as  the leading authority in the nation on juvenile homicide. Chalmers has interviewed over 200 teen killers and school shooters, and has been studying teen murders as well as youth culture in general for the past 25 years.

Chalmers will be joined by Joe Shillaci  from the A&E network series "48 hours." Long says the seminar will look at why teens kill, warning signs of teen violence and what can be done to keep schools safe. Long says tickets for the seminar are available now at the civic center website.