If your news organisation uses javascript for its comments, or for any other part of the site, you may well be advised to start doing some testing.

Malcolm Coles, the Editor of Which.co.uk, has been highlighting some of the problems with the technology for search engine optimisation and accessibility (the two are often closely related) on his blog.

Coles first posted about the Guardian’s redesigned comments system, which, Coles says, breaks the newspaper’s own accessibility policy by relying purely on javascript and leaves them open to legal action:

“the Guardian is arguably in breach of the Disability Discrimination Act, which ‘makes it unlawful for a service provider to discriminate against a disabled person by refusing to provide any service which it provides to members of the public’.”

The Guardian’s announcement of the changes, Coles’ comments, and their responses can all be seen here.

In a second post, Coles noted that Johnston Press Digital Publishing’s reliance on javascript meant that a search on Google News for their pages returned a result like this:

And, following some discussion in the comments on a story here, in a third post Coles tackled third party commenting systems such as Disqus, IntenseDebate and Sezwho:

“Google doesn’t bother to run javascript when it indexes a page. And the problem with these commenting systems is that they use javascript to do their fancy functionality – but also the basic stuff like actually showing the comments … You can prove that Google isn’t indexing the comments for Disqus and IntenseDebate by searching for the name of the person with the first comment on the page – when you do, you get no hits. (EG this search returns a results for the disqus page, not the simpable one).”

And search engine rankings aren’t the only things to get hurt. Coles outlines several other side effects of using javascript for comments:

• “Mobile devices can’t see it reliably (lots of mobile phone browsers don’t use javascript so the comments sections can’t be used).
• “The pages take ages to load (all that unnecessary javascript).
• “The comments are sloooow to appear Once the page has loaded, the JS runs and the comments are loaded into the page. This is slow. Really slow.”