According to BBC guidelines, the physical and emotional welfare of minors must be protected in broadcasts. Ofcom also has guidelines to ensure minors are kept safe, such as only airing some news stories at appropriate times. Radio broadcasters must consider legal constraints before airing, such as not naming young offenders to protect them. The law of defamation was created to protect a person's reputation, such as when David Beckham lost a libel case over false claims made about him in a magazine article. On election days, the BBC cannot report on campaigns or other matters relating to the election once polls open to avoid influencing votes. The Official Secrets Act makes it a criminal offense to leak or disclose information relating to national security