More relevant information...
Having now had time to look through the Explanatory Notes here's some more information regarding this offence:
The explanatory notes on the "Communicating Indecently" section say:
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23. Both subsections (1) and (2) provide that the offences are committed only where the victim did not consent to the activity and the perpetrator had no reasonable belief that the victim consented.
[...]
26. Subsection (3) provides that an offence under subsection (1) or (2) is committed only where the perpetrator’s purpose is to obtain sexual gratification, or to humiliate, distress or alarm the victim.
[...]
28. Subsection (5) provides a test for whether an activity is sexual for the purposes of this section. This is effectively the same as the test used in section 2 – see paragraph 13 above.
(Paragraph 13 says: [...] It provides that an activity is sexual if a reasonable person would, in all the circumstances of the case, consider it to be sexual.)
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This suggests that it would require the prosecution to demonstrate that the communication was sent "to obtain sexual gratification" or "to humiliate, distress or alarm the victim".
This is unlike the UK's "Allowable Defence" for possession of "Extreme Pornography" in the Criminal Justice and Immigration Act that the image was not owned "for sexual arousal", ie a much more stringent test.
I still think that 10 years is ridiculously excessive, but perhaps people might like to stop their knees jerking when they read an article like this and try to ascertain a few of the facts first...