In a clear case of "oops", my otherwise realiable newspaper reported this morning that the ECtHR had ruled that prisoners could not be denied the right to vote, at least not categorically. While they did in fact rule that, the ruling in question is more than five years old. (The 2004 panel judgement is here, and the 2005 Grand Chamber judgement is here.) The article in question is only a small one-columner, and it is easy to see how the error occurred. The final byline, which for such articles usually refers to the wire service that provided the story, refers to the BBC, presumably to this article. Clearly the responsible copy editor overlooked the part of the story that explains that the ECtHR judgement is five years old, and that the UK government waited until now to comply, despite a resolution from the Council of Europe's Committee of Ministers from December 2009, warning them to make sure the new elections would comply with the ECHR. In the intervening years, the Labour governments had fun with various consultations, the instrument beloved by governments the world over to avoid actually doing something.
As to the substance of the case, suffice it to say that prisoners voting presents some unique difficulties in an electoral system with single candidate constituencies like the UK, but nothing that can't be overcome by having them vote in their home constituency. Otherwise, I think the unique vulnerability of prisoners to the whims of the political system is reason enough to make sure that their right to vote is only taken away in rare circumstances. (And don't even get me started about the common US practice of denying convicted felons the right to vote even after they've been released from prison.)