Here is an extract from the box label of the 1871 census discs from S&N - "Images may be used only for purposes of research, private study or education". You note they refer to images and not information. Secondly, assuming I copy an image to you. Does this come from the fiches held at the FRO or from their discs. Thirdly, if I do so, am I using it to educate you? to assist you in your private study? to assist you in your research or our joint research?
That is just one example. It is not necessary to run scared or consult your lawyer before you make a posting. In order to secure a criminal conviction [referred to in another posting] it is usually necessary to prove criminal intent. Devoid of criminal intent you are not likely to be prosecuted successfully.
If I make a copy of one of the S&N discs and give it to you or sell it you then I am indeed liable to prosecution as that is piracy and I had a clear intent to deprive them of some benefit of their investment of time and money in the publication.
Before anyone will launch a civil action against you they would usually consider the prospects of success and the likely recovery. Normally, in this type of matter, they would require you to desist. If you agreed then it is hardly likely that any civil suit could succeed.
What one must be aware of is that the fact that someone copies data that is in the public domain they cannot claim copyright to that data - only to the form in which it is presented.
So, I repeat - so sue me!