Mark O’Brien Legal are Australia’s leading defamation law firm.
We act for both plaintiffs (claimants) and defendants (including mass media publishers), giving us a unique perspective that strengthens our strategy and advocacy.
For a claimant, false or damaging statements can have profound consequences, tarnishing reputations, harming careers, and eroding trust in both personal and professional spheres. In today’s digital age, where information spreads instantly, the stakes are even higher as defamatory content can remain accessible indefinitely, impacting future opportunities and relationships.
Protecting your reputation isn’t just about addressing the immediate harm – it’s about preserving your credibility, livelihood, and standing in the community.
That’s why swift, strategic action is essential to mitigate damage, restore your good name, and secure long-term peace of mind. In a 2025 analysis conducted by Australia’s leading media law publisher, Mark O’Brien Legal had achieved the highest average defamation awards for clients amongst defamation law firms in Australia for the period 2020 – 2024.
For a publisher, whether corporate or an individual, a defamation claim can have far-reaching reputational and financial impacts.
We have a proven track record in successfully defending the rights of publishers over published material, from mass media publishers to individuals posting on social media.
We provide round the clock pre-publication advice for publishers, including one of Australia’s leading online news websites.
No matter whether you are a plaintiff or a publisher, Mark O’Brien Legal have the unique skills to aggressively and strategically fight to protect your interests.
With unmatched expertise in defamation, other forms of media law, and reputation management, we act swiftly and decisively in high-stakes situations.
Clients rely on us to deliver strategic guidance in critical moments, whether it’s making or responding to defamation claims, providing reputation management advice and coordinating with internal teams and external media advisors.
Our services span the full spectrum of reputation management, from providing advice and assistance prior to publication to post-publication remedies and crisis management.
Our track record for aggressive representation has established us as a trusted partner for media companies, social media platforms, and individuals or corporations making or facing reputational threats.
Available around the clock, we work to resolve crises efficiently, negotiate settlements where possible or litigate assertively when necessary.
With a fearless, results-driven approach, we ensure that our clients’ interests are fully and aggressively protected.
As the leading Media and Defamation law firm we have successfully acted in many high-profile cases including acting for: