Joshua Rozenberg explained: "If you can show that somebody knew that there was a court order in force, as this man last week, who was very nearly sent to prison - in the end he got a suspended sentence and a hefty financial penalty.
"But if you know that there is a order saying you can't publish a picture of Jon Venables, then it is obviously more easy for the Attorney General to prosecute you."
Careless tweets have landed a host of celebrities in trouble in the past with comedian Alan Davies, Sir Bob Geldof's daughter Peaches and Sally Bercow all finding themselves in legal difficulties due to their online posts.
Social media users have also found themselves in contempt of a court - nine people admitted naming the woman raped by footballer Ched Evans on Facebook and Twitter.
The Attorney General said he was publishing legal guidance notes previously only issued to the media to "help stop people from inadvertently breaking the law."
Dominic Grieve QC said: "Blogs and social media sites like Twitter and Facebook mean that individuals can now reach thousands of people with a single tweet or post. This is an exciting prospect, but it can pose certain challenges to the criminal justice system.
"In days gone by, it was only the mainstream media that had the opportunity to bring information relating to a court case to such a large group of people that it could put a court case at risk.
"That is no longer the case and is why I have decided to publish the advisories that I have previously only issued to the media.
"This is not about telling people what they can or cannot talk about on social media - quite the opposite in fact, it's designed to help facilitate commentary in a lawful way.
"I hope that by making this information available to the public at large, we can help stop people from inadvertently breaking the law, and make sure that cases are tried on the evidence, not what people have found online."
The Attorney General will publish legal guidance notes online to help prevent Facebook and Twitter users from breaking the law by inappropriately commenting on court cases.
The Government's chief legal adviser Dominic Grieve QC will in future issue previously unpublished advisory notes in a bid to stop social media users from committing a contempt of court.
He said the move was designed to make sure that fair trials take place and will apply to court cases in England, Wales and Northern Ireland.
The advisories, which have previously only been issued to the media, are being put into the public domain so people avoid legal pitfalls by commenting on court cases in a potentially prejudicial manner.
The advisories will be published on the Attorney General's Office (AGO) section of the gov.uk website and also through the AGO's Twitter feed - @AGO_UK.
Complaints of crimes involving Facebook and Twitter have increased 780% in four years, resulting in around 650 people being charged last year, police figures show.
The phenomenon of social networking crime was comparatively minor in 2008 with 556 reports made to police, according to the statistics released by 29 police forces in England, Scotland and Wales under the Freedom of Information Act.
But this year 4,908 offences in which the two sites were a factor were reported.
Police forces were asked to provide the number of crime reports in which either Facebook or Twitter was a key factor. This included offences committed on the sites, such as posting abusive messages, and those which were provoked by postings, including violent attacks.
A total of 653 people faced criminal charges over the allegations this year, according to the forces which responded.
Great Manchester Police charged the highest number of people, at 115.