An anonymous reader writes "A teenager from Dorset, England was arrested for sending a Twitter message to Olympic athlete Tom Daley saying: 'You let your dad down i hope you know that.' Police arrested the 17-year-old boy as part of an investigation into 'malicious tweets' after Daley and his teammate missed out on a medal. Daley's father died from cancer last year. While it is rarely used and the police have not indicated whether they are pressing charges, the Communications Act 2003 s.127 covers the sending of improper messages. Section 127(1)(a) relates to a message that is grossly offensive or of an indecent, obscene or menacing character. Sean Duffy was convicted and sentenced earlier this year for similar comments. I look forward to tens of thousands of arrests across England over the next few days as all public remarks which may cause offense, regardless of their target, are investigated by the law." According to the Guardian, another (since deleted) tweet threatened Daley with drowning, but the law doesn't require threats of violence for an arrest to be made.