To begin with, from the point of view of truth, it is not correct that Jonathan took over from the Obasanjo administration; Umaru Yar’Adua did. More importantly, the argument conveniently disregards the inescapable reasons precluding Jonathan (and Yar’Adua too) from probing the Obasanjo administration. All three administrations were PDP governments, and it seems inconceivable that one PDP government should probe another. Standing above all this is the circumstance that Obasanjo was the father of the PDP (albeit self-proclaimed), its leader for life and, on the cessation of his tenure as President, the Chairman of the Party’s Board of Trustees (BOT), with power to direct the PDP State Governors. It was he who chose Yar’Adua as the Party’s presidential candidate in the 2007 election, with Jonathan as his running mate, and foisted the two of them on the Party and the country. Thus, there was simply no way Jonathan (and Yar’Adua too) could have probed the Obasanjo administration.

Yet, the existence of factors precluding Jonathan from probing the Obasanjo administration does not remove the compelling need for such a probe. For the PDP, as a ruling Party for 16 years (1999–2015), was a government characterised by so much evil, including corrupt practices and impunity, which reached their zenith during the eight years of Obasanjo’s rule. The country yearned for deliverance, for a change from PDP rule to rule by another party. The deliverance, the change, came with the March 2015 presidential election that flushed out the PDP, replacing it with APC as the ruling party. (The personal characteristics of the man heading the APC Government, President Buhari, as well as those of former President Jonathan, raise an altogether different issue, which makes choosing between them a perplexing matter.)
As to how far it should go in probing past administrations, the limit is set by the facts on the ground, and by the magnitude and enormity of corrupt practices during each of the successive administrations that is within common knowledge. The Gowon administration (1967–1975) has been investigated by the Mohammed/Obasanjo regime, the Shagari administration (1979–1983) by the Buhari/Idiagbon regime; the Abacha administration (1994–1998) by successor regimes. That leaves the Babaginda (1985–1993) and Abdulsalami Abubakar (1998–1999) regimes as the past regimes that need to be investigated, in addition of course to Obasanjo’s administration (1999–2007).