Licensees have been warned to carry out risk assessments if an attack takes place on their premises.
This comes after the Metropolitan Bar in London's Old Park Lane was taken to court by the victim of a stabbing attack.
The victim brought a case against nightclub and hotel owner Comojo on grounds that it failed to take appropriate steps to protect guests.
However, the case was dismissed after the Central London County Court ruled that the venue had not failed the steps it needed to take protect its customers.
John Gaunt of law firm John Gaunt & Partners said that the case raised concerns about the duty of care as a result of third party actions.
He said that licensees must make sure they carry out a risk assessment if an attack takes place, document that assessment and "ensure staff are trained in an appropriate response". If licensees take no action, he said it would be more difficult for an operator to avoid a pontential liability.
However, whether an owner is liable will "depend on the nature of the premises and its clientele", explained Gaunt.
"Operators can't assume that nothing will happen on their premises," said Gaunt. "They need to be responsible of what goes on."