> a person is guilty of an offence if he—
> (a)sends by means of a public electronic communications network a message or other matter that is grossly offensive or of an indecent, obscene or menacing character; or
> (b)causes any such message or matter to be so sent.
I suspect the former is also true, but am not well-read in that area
> A person is guilty of an offence if, for the purpose of causing annoyance, inconvenience or needless anxiety to another, he—
> [F1(a)sends by means of a public electronic communications network, a message that he knows to be false,]
> [F1(b)causes such a message to be sent; or]
> (c)persistently makes use of a public electronic communications network.