The Bar Standards Board (BSB) has amended its guidelines to clarify what barristers can say online.

The guidance details a “non-exhaustive” set of examples of the types of social media conduct that could fall foul of the regulations, including “comments about judges, the judiciary, or the justice system which involve gratuitous attacks or serious criticisms that are misleading and do not have a sound factual basis”.

But free speech advocates have warned the guidance fails to explain where the line is between robust debate and discrimination or attacks.

The BSB said the guidelines “make clear that it is the manner in which barristers express their views that is more likely to concern us rather than the substance of that view”.

It does, however, add: “Although the substance of a barrister’s view may also raise regulatory issues.”

Mark Neale, the BSB director general, said the guidelines provide “greater clarity rather than a significant change”.

He added: “The documents explain more clearly how we will apply the existing rules and how we try to balance barristers’ obligations under the BSB Handbook with their rights under the Human Rights Act 1998.”

Toby Young, founder of the Free Speech Union, said: “This guidance represents a good-faith effort to balance barristers’ right to freedom of expression with the need to protect the reputation of the profession, but the problem is the language used by the BSB when describing what it has a ‘regulatory interest’ in is unavoidably imprecise … for instance, what is an acceptable criticism of the justice system and what is ‘gratuitous’?”

Nick Vineall KC, chair of the Bar Council, said: “We think that the BSB has struck the appropriate balance, and it is right that the regulator focuses on the use of language that is seriously offensive, discriminatory, bullying or harassing.”