They were imprisoned in Dhaka Central Jail after the 15 August 1975 Bangladesh coup d'état and the assassination of Sheikh Mujibur Rahman and his family members.

[5][6] Hashem was appointed to a diplomatic post in Ottawa, Canada, by the government of Lieutenant General Ziaur Rahman.

[9][10] On 8 November 1998, Judge Golam Rasul of the Dhaka Sessions sentenced Hashem and 14 other individuals in the Sheikh Mujibur Rahman assassination case.

After the verdict was read his home in Don Chamber area, Narayanganj District, Bangladesh was attacked and vandalized.

Showkat Hashem, his brother and Bangladesh Nationalist Party leader, filed a case against Shamim Osman and 81 other people over the attack on the house on 14 December 2001.