Manmohan Singh, during his tenure as Prime Minister, was often referred to as "mute" by his opponents. Even after stepping down from the position of Prime Minister and joining the Opposition benches, there was not much change at the outset. However, when he first criticised the demonetisation by the Modi Government as a "planned massacre" and "legalised plunder" in Parliament, his measured tone resonated throughout the country. Manmohan Singh, who had been a staunch critic of the BJP government’s economic policies, was widely noticed after this.

During his tenure as Prime Minister from 2004 to 2014, the country witnessed several major scams and corruption allegations. The scandals like the Kochi port, 2G spectrum and Commonwealth Games provided ammunition for the Opposition. While neither Manmohan Singh nor his office was directly accused of corruption, his silence in these cases was used against him by his opponents.

Even after stepping down from power, Manmohan Singh maintained a calm and silent stance both in Parliament and outside. One notable occasion was in November 2016, when he spoke in the Rajya Sabha about demonetisation, weeks after the decision. Manmohan Singh, a globally recognised economist, described demonetisation as an "organised plunder”. This strong statement resonated everywhere and then the country got to see a very strong critic of BJP Government's economic policies.

The government had argued that, while there might be short-term problems due to demonetisation, it would lead to long-term gains. However, Manmohan Singh’s criticism echoed the words of economist John Maynard Keynes, who had said, "In the long run, we are all dead”.

Manmohan Singh's expertise was strategically utilised by the Congress Party to criticise the shortcomings of the Modi Government policies. His critiques were pivotal when the Goods and Services Tax (GST) was implemented, and also when he opposed significant budgetary decisions.

During the Covid-19 lockdown, Congress formed an 11-member consultative group to discuss the issues the country was facing. Manmohan Singh was appointed as the head of the group, alongside former US President George Bush. When the government froze the increased Dearness Allowance (DA) for government employees and soldiers due to revenue shortages caused by the pandemic, Manmohan Singh strongly opposed it. He described the government's actions as unnecessary and detrimental to government officials and military personnel.