Explanation:

Meerut Conspiracy case: The Meerut Conspiracy case started with the issuing of arrest warrants against 31 Communists and other persons on 15th March 1929. The charges were that these persons conspired to overthrow the British Government of India through strikes and other militant methods. The arrested included almost all the known communists including Muzafr Ahamed, S.A.Dange, S.V.Ghate, Dr.G.Adhikari, P.C.Joshi, S.S.Mirajkar, Shaukat Usmani, Philip Stratt and others.

Lahore Conspiracy Case: On 8th April 1929, Bhagat Singh and Batukeshwar Dutt went to the Central Legislative Assembly and threw a bomb at government benches and raised slogans of Long live the Revolution. There were no casualties and probably none was intended. Bhagat Singh and Dutt surrendered and were taken into custody. Many other members of the association were arrested later and a bomb workshop unearthed. Except for Chandra Shekar Azad all the prominent members were arrested and charged with the murder of the Superintendent of Police of Lahore also.The prisoners were brutally treated in jail. Jatin Das died after a hunger strike lasting 64 days. Bhagat Singh, Rajguru and Sukhdev were later sentenced to death. There execution led to massive protests all over the country.
Alipore Conspiracy case: there were raids on the members of the Anushilan Samiti. The documents such as letters were seized from the house of Arubindo Ghosh and he was arrested and lodged in Alipore Jail. Khudi Ram Bose was meanwhile arrested. The trial continued two years and finally Khudi Ram was hanged. Chitranjan Das, one of the prominent barristers of the day defended and saved Sri Arubindo. Barindra Ghosh and Ullaskar Dutt were sentenced to rigorous imprison and they were released in 1920