I too would be interested to know if this cyclist was wearing a helmet, but not with a view to crusading in favour of them: it would be useful if all news reports of collisions and injuries involving cyclists stated whether or not a helmet was being worn. This would demonstrate to the public that a)helmet wearing does not prevent accidents (an incredible assumption made by many who have asked me why I do not wear one), b) they provide no protection whatsoever to 95% of the cyclist's body (an obvious fact to which many seem oblivious), and c) they provide very little additional protection to the small part they do cover.
If such information was widely available it would help to counteract the propaganda in favour of wearing helmets which actually has a detrimental effect on cyclists' safety: most motorists on seeing a cyclist ahead, wearing a helmet, and recalling the propaganda, subconsciously assume that the cyclist is just as well protected as they are in their tin box and overtake recklessly, while others, a self-righteous minority, perhaps, decide to teach the cyclist a lesson for ignoring the propaganda and pass in a similarly reckless manner.
There is, fortunately, a third category, who on seeing a cyclist ahead, bare-headed, drive extra carefully in his or her vicinity, something I have proved if only anecdotally, by sometimes wearing a cap, and sometimes not. Even a woolly bonnet suggests to some motorists that a cyclist is "protected", whereas a bare head suggests vulnerability. Bareheaded female cyclists with long hair, (or males who don a long blond wig) will notice this effect most, as the male motorist, obeying a primeval instinct, will often regard the female (or apparently female) cyclist as weak and in need of care and protection.