[citation needed] Shahnawaz was studying in Switzerland when Zia ul Haq's military regime executed his father in 1979.

Prior to the execution, Shahnawaz and his elder brother Murtaza Bhutto had embarked on an international campaign to save their father's life, but it was to no avail.

[citation needed] Shahnawaz and his brother Murtaza Bhutto married two Afghan sisters, Rehana and Fauzia.

No one was brought to trial for murder, but Shahnawaz's wife Rehana was considered a suspect by the French authorities and remained in their custody for some time.

[citation needed] Shahnawaz is believed to have helped organize a group dedicated to overthrowing the regime of President Mohammed Zia ul-Haq, through links to Al-Zulfiqar increasingly active in Pakistan at that time.