Some of the more offensive remarks were taken down, the house heard
A Labour peer has condemned a Facebook entry which includes the addresses of serving police officers as an "intolerable attack".
Lord Mackenzie of Framwellgate said the group had identified and threatened Northumbria Police officers.
Speaking at question time in the House of Lords, he told peers that it was an abuse of the freedom of speech.
But the house heard encouraging self-regulation was the only realistic way to deal with US-based Facebook.
Lord Mackenzie, the former president of the National Police Superintendents' Association, said: "The group is posting messages identifying individual police officers and their families and addresses, sometimes with photographs, and threatening them with violence.
"This is an unacceptable abuse of freedom of speech and an intolerable attack on frontline police officers and their families - officers who are doing a difficult and dangerous job - and amounts to an undermining of the rule of law in a liberal democracy."
Broadcasting minister Lord Carter of Barnes said he considered the content to be "deeply unacceptable", but said that "aggressive, restrictive statutory regulation is inappropriate - it simply does not work".
He said: "There are some very specified offences where there is an immediate 'take down' requirement on any service provider or social networking site - that includes child pornography or race-hate abuse as two examples.
"We have worked with the service providers to agree a set of guiding principles."
But he said that different sites and providers had different principles.
Some of the more offensive remarks, such as racist comments, have since been taken down within the conditions of service of the site, he added.
A police spokesman said: "Northumbria Police is aware of this group and has previously asked that copyright material and details of individual officers be removed.
"Although the content of the group may be considered offensive, Northumbria Police supports the right of individuals to express their views provided they do not break the law."