Leo Goatley described reports that claimed Frederick West had tortured his victims in remote farmhouses as "speculative" and "inadmissible".
"I regard my client as entirely innocent and that Frederick West was responsible for these killings," he said.
"Having said that, the detailed speculation in the press upon the circumstances of this dreadful case cannot be helpful to my client. Such detailed speculation in the Sunday press may well be taken as fact by the public, including potential jurors."
West, found hanging in his cell in Winson Green prison, Birmingham, on New Year's Day, was charged with murdering 12 women and girls. Rosemary West, 41, who is being held at Pucklechurch Remand Centre near Bristol, was jointly charged on nine of the murders.
Last week, Mr Goatley obtained an injunction against Scott Canavan, a former legal clerk, following reports that he was offering to sell handwritten notes of police interviews with Frederick West for £105,000.
The court order, banning publication or broadcast of the material, was also granted against Mirror Group.
West's son, Stephen, was yesterday quoted in the News of the World describing how his father allegedly admitted the murders to him during prison visits.
Mr Goatley said: "At some stage it will be a judicial decision whether my client can get a fair trial in view of the overwhelming press coverage which we regard as prejudicial. It is the Attorney General's responsibility to safeguard those proceedings."
In the light of West's death, the Crown Prosecution Service is reviewing the case against Rosemary West. It hopes to make a decision by the end of the week.
"We are deciding how best to proceed," said a spokeswoman. "Clearly any changes must be considered. We are looking at the evidence to see if there is a realistic prospect of conviction and if it is in the public interest. If these two criteria are met wewill proceed."
Inspector David Morgan, press spokesman for Gloucestershire Police, said: "The continued media attention and the way of reporting speculative and inaccurate information in the Cromwell Street investigation is still of concern.
"This has been brought to the attention of the Crown Prosecution Service and the Attorney General's office on a regular basis. The content of some of the tabloid Sunday newspapers is a further example."
Meanwhile, the Bishop of Hereford, the Rt Rev John Oliver, said yesterday that he could see no reason why Frederick West should not be buried in his village church.
The parish council of Much Marcle in Hereford and Worcester voted to ask the parochial church council to refuse permission for West's burial at St Bartholomew's if it is requested. Councillors fear his headstone may be desecrated and many villagers are upset by the idea of West resting in the same churchyard as their relatives.
But Dr Oliver, who may have to rule on the issue, told Radio 4's Sunday programme: "I think there is a difference between someone who is convicted and someone who isn't. They are two different cases. But I think in either case there would be no reason why a person should not be buried in a churchyard.
"Nobody is outside God's mercy or the possibility of God's forgiveness."