The recent spate of violent crimes involving firearms has led to a growing chorus of demands from certain quarters for the government to reinstate preventive laws.
But Najib disagreed with the demands, saying he will not reinstate the powers to detain individuals without trial that he has abolished.
"We are doing our best to find a good balance to ensure that human rights are not affected but to defend public interest as well," he said.
"This is what is needed for a more matured society," he said, adding that it was a fine juggling act.
Former Prime Minister Tun Dr Mahathir Mohamad had warned that Malaysians would have to pay a price for the more liberal brand of democracy they were demanding.