Copyright of images of works of art out of copyright

The copyright situation on wikipedia is quite interesting. They use images from artists represented in National Museums and Galleries and they claim them as public domain on the basis that the artist has been dead for over 70 years.
I'm guessing the Galleries would probably counter claim they are copyrighting not the original painting, but the photograph of it. The photographer is still alive and therefore copyright is valid.

But these images are still up on wikipedia. Is this because they turning a blind eye?

Or is it that they accept wikipedia's claim that copyright of a faithful reproduction of the original 2d image is not valid.

This is the page that explains it
http://commons.wikimedia.org/wiki/Commons:When_to_use_the_PD-Art_tag

Of course some of the images on wikipedia use reproductions which were made long enough ago to be out of copyright.

However, reading on - reusing these images in the UK is risky as our courts will probably accept that copyright of a copy is allowed. So using these images on wikipedia is ok reusing them elsewhere in the uk is not.

reading
Commons:When to use the PD-Art tag - Wikimedia Commons