Section 127(1) of the Communications Act started life as section 10(2) of the Post Office (Amendment) Act 1935. Here is a comparison of the two:
Section 127(1) of the Communications Act 2003:
Section 10(2) of the Post Office (Amendment) Act 1935 [ source - Andrew Sharpe]:
If any person-The original intention of Parliament was to protect telephone operators (historically female) against exposure to lewd callers. The amendment extended this protection to the general public with a view to protecting the integrity of the public telephone network, which at the time was publicly funded as well as being provided for the benefit of the public. It was re-enacted several times throughout its life and took its latest shape in 2003. In both forms and all throughout you will see the reference to indecent and obscene. So what about telephone sex chat lines? Surely this falls afoul of Parliament's original intention to protect the integrity of the public telephone network.
The case law touches on this point briefly. At the very end of DPP v Collins, Lord Brown makes reference to telephone chat lines but rather unhelpfully leaves this as a matter "for another day".
...I am finally persuaded, however, that section 127(1)(a) is
indeed intended to protect the integrity of the public communication
system: as Lord Bingham puts it at paragraph 7 of his speech, “to
prohibit the use of a service provided and funded by the public for the
benefit of the public for the transmission of communications which
contravene the basic standards of our society”. (Quite where that leaves
telephone chat-lines, the very essence of which might be thought to
involve the sending of indecent or obscene messages such as are also
proscribed by section 127(1)(a) was not explored before your Lordships
and can be left for another day.)
And the desire to protect the integrity of the public communications system is precisely why the sending of a qualifying message is enough to breach the law, regardless of whether it is received. Lord Brown's remarks here more than anything else highlight the absurdity of this legislation in the modern day. Unless the meaning of indecent has changed or we regard a telephone sex chat line as a content service, as defined in section 32 of the Act, it would clearly fall afoul of this law. I can't see that either of these conditions is true. It really is a shame that the Lords did not consider such use cases in 2006. It might have saved us a lot of bother now.