Hello. Rowlatt act is the one that is passed during British time. This gave power to police to arrest any person without any reason. Police can just come and arrest a person without having any proper orders or reason. Since patriotism and nationalism was increasing by then, britishers passed this act to curb the nationalism in people. This act was opposed by mahatma Gandhi because not everyone should be punished in response to isolated political crimes. So Indians went on strikes, suspended businesses, held meetings. It was named as black act

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Nikhitha