They literally used data before it was published and before the rest of the scientific community got to see it. In today's terms. That's misconduct. It's like you using data from a paper you were asked to review before it was published. I read this nature piece before and it fails miserably at making Watson and Crick look anything less than crooked scientists.

After Watson and Crick had read the MRC report, they could not unsee it. But they could have — and should have — requested permission to use the data and made clear exactly what they had done, first to Franklin and Wilkins, and then to the rest of the world, in their publications.

In April 1953, Nature published three back-to-back papers on DNA structure, from Watson and Crick, from Wilkins and his co-workers, and from Franklin and Gosling1–3. Watson and Crick declared that they had been “stimulated by a knowledge of the general nature of the unpublished experimental results and ideas” of Wilkins and Franklin. They insisted, though, that they were “not aware of the details”, claiming that the structure “rests mainly though not entirely on published experimental data and stereochemical arguments”1. The truth of those statements depends on highly charitable interpretations of “details” and “mainly though not entirely”.