Concerns have been raised that the Government's definition of extremism is restricting free speech and legitimate debate.
Sara Khan, head of the Commission for Countering Extremism, said that while hateful extremism was a real problem, people needed to be free to criticise and "even be offensive", The Telegraph reports.
She outlined her case in a new report this week, Challenging Hateful Extremism, in which she described the Government's strategy as "unfocused" and warned that it was failing to effectively address the problem.
"We must continue to protect and preserve freedom of expression," she said.
"This includes our right to be radical, to protest and even be offensive. I believe we need more speech not less to counter hateful extremism; more discussion and debate is vital."
In an article for The Telegraph, Khan clarified: "The Commission describes hateful extremism as behaviours that incite and amplify hate or engage in persistent hatred or make the moral case for violence."
Khan was appointed to examine the threat of extremism in England and Wales following terrorist attacks in London and Manchester in 2017.
The report is based on 18 months of evidence-gathering, including some 3,000 responses to the inquiry. In official figures, three-quarters of the responses that came from members of the public said that the Government's current definition of extremism was "very unhelpful" or "unhelpful".
Just over half (52%) of all respondents had witnessed extremism in some way. Of these, two fifths (39%) said they had seen it in their local area while just under half (45%) reported seeing it online.
At the time, Khan said that the Government needed to address extremism while upholding democracy.
"We must guard our right to debate, protest and offend. We should use the word 'extremism' with caution. But I believe we can, and must, do more," she said.
She added: "I believe we need to put forward a positive vision of countering extremism which is about upholding our democratic society and our great country."