Congress prohibits the Centers for Disease Control and Prevention from using any of its funding to promote or advocate for gun control. NPR science correspondent Nell Greenfieldboyce looked into how that makes it difficult for the CDC to talk frankly about the role guns play in suicide. If you or someone you know may be considering suicide, contact the National Suicide Prevention Lifeline at 1-800-273-8255 (En Español: 1-888-628-9454; Deaf and Hard of Hearing: 1-800-799-4889) or the Crisis Text Line by texting HOME to 741741. Follow host Maddie Sofia on Twitter @maddie_sofia. Email the show at shortwave@npr.org.