During the protests following the disputed 2008 Armenian presidential election, there were expectations that Grigoryan and another deputy defense minister, Gagik Melkonyan, would encourage the army and the Yerkrapah Volunteer Union to intervene in favor of the protestors led by ex-president Levon Ter-Petrosyan. Ter-Petrosyan declared on 21 February 2008 that he had met with Grigoryan and Gagik Melkonyan and that they had agreed to join the protestors. The protests were suppressed using the army on 1 March 2008, resulting in the deaths of 10 people. Then president-elect Serzh Sargsyan stated on 13 March 2008 that he was "deeply regretful and hurt that he [Manvel Grigoryan] made an attempt to enter politics and disobey his commander-in-chief." On 2 April 2008, Grigoryan was dismissed from the post of deputy defense minister by President Robert Kocharyan. In an interview given in 2012, Grigoryan stated that although there were people who tried to involve the Yerkrapah Union in political processes during the 2008 protests, he worked to keep the Yerkrapah Union out of politics at the time.
