The first is Baroness Kennedy of the Shaws and the second Baron Hattersley of Sparkbrook, or Lady Kennedy and Lord Hattersley for short. Lady Helena Kennedy would be correct only if she were the daughter of a duke, earl or marquess, Lord Roy Hattersley only if he were a younger son.
However, I would allow Lady (Helena) Kennedy and Lord (Roy) Hattersley for clarity of identification.
In fact, both hate their titles being used at all, as Labour peers often do. I have little patience with this attitude. If people do not want to be called lord or lady, then they should refuse the offer of a peerage along with its law-making powers.
Does the correct title matter? I think it does, because to use the wrong title for Kennedy or Hattersley gives a seriously inaccurate impression of the kind of people they are and of their power and influence. Perhaps more importantly, the consistent misuse may lead readers to believe that, say, Lord Charles Seymour, the teenage younger son of the Duke of Somerset, is a person of greater consequence than he actually is.
I admit to pedantry, and as the New Statesman rarely wrote about younger sons of dukes, the dangers of misleading readers were small. It was just that the error offended my eye and signified general sloppiness and ignorance. The rule was not difficult to learn. Flouting it suggested a cavalier attitude to getting things right.
My feelings about the greengrocer's apostrophe - apple's, pear's and so on - are similar. I cannot think of many occasions where this error would lead to misunderstanding, least of all when buying fruit and vegetables.
Yet I recoil from it because it suggests the user does not care.
Greengrocers who misplaced apostrophes were, in my experience, the ones who gave you rotten fruit and excused the lack of, say, purple-sprouting broccoli because "there's no demand for it, guv".
So I applaud the Qualifications and Curriculum Authority (QCA) which proposes to deny a grade C or above in GCSE English to candidates who fail to use apostrophes and other punctuation correctly. We pedants, with our almost aesthetic objections to misplaced or missing apostrophes, may be a diminishing band. But we tend to judge people by their commas.
One job application or one sales brochure looks much like another. Bad punctuation, signifying carelessness, is a good way of narrowing down the choice of employees or washing machines. In many cases, good punctuation, alongside good spelling and grammar, will be the first gateway to getting a job or making a sale.
The QCA is right to propose importing this into the exam system. It may not be fair, but there it is. The point is, we should be giving our children a marketable skill.
Some people, many of them quite important, care about punctuation. I do not believe exam candidates will struggle to learn and apply the rules. If told these rules are important, most will easily learn them, just as most easily learn the protocols for calling up websites or sending emails, where a single misplaced dot will cause the computer to bark "not found".
English teaching should be about using the right language in the right circumstances. Punctuation matters for some significant audiences.
I am happy to spare GCSE candidates learning the correct titles for peers because these will rarely matter. But in case they want a job from a crusty old pedant like me, I would make the titles a requirement in journalism training.