From 1979 to 1980, at the rank of colonel, Buhari (class of 1980) attended the US Army War College in Carlisle, Pennsylvania, in the United States, and gained a master's degree in Strategic Studies.

[55] The law further stated that offending journalists and publishers will be tried by an open military tribunal, whose ruling would be final and unappealable in any court and those found guilty would be eligible for a fine not less than 10,000 naira and a jail sentence of up to two years.

[66] In another prominent case of April 1985, six Nigerians were condemned to death under the same decree: Sidikatu Tairi, Sola Oguntayo, Oladele Omosebi, Lasunkanmi Awolola, Jimi Adebayo and Gladys Iyamah.

[69] His regime drew criticism from many, including Nigeria's first Nobel Prize winner Wole Soyinka, who, in 2007, wrote a piece called "The Crimes of Buhari"[70] which outlined many of the abuses conducted under his military rule.

[81] Buhari was the CPC presidential candidate in the 2011 election, running against incumbent President Goodluck Jonathan of the People's Democratic Party (PDP), Mallam Nuhu Ribadu of Action Congress of Nigeria (ACN), and Ibrahim Shekarau of ANPP.

He also gave support to enforcement of Sharia law in Nigeria's northern states, which had previously caused him political difficulties among Christian voters in the country's south.

[102] Buhari's key advisers include: his nephew Mamman Daura, businessman Ismaila Isa Funtua, political operator Baba Gana Kingibe, Abba Kyari the Chief of Staff to the President; and from the late stages of his first term, Boss Mustapha the Secretary to the Government of the Federation.

A result of this has created the outcome of political considerations as an important factor in nominating ministers as local party officials lacking in merit jostle for cabinet positions.

[104] The cabinet include two wealthy former governors from the Niger Delta, Timipre Sylva and Godswill Akpabio who were originally members of the opposition party PDP and fourteen retained ministers some of whom critics alleged had performed poorly or having a close relationship with a corrupt past Head of State.

[104] In May 2016, Buhari cancelled a two-day visit to Lagos to inaugurate projects in the state but he was represented by the Vice-president Yemi Osinbajo after citing an "ear infection" suspected to be Ménière's disease.

[106][107] This happened days after the Presidential Spokesman Femi Adesina was quoted as saying Buhari was "as fit as fiddle" and "hale and hearty", to much discontent and criticism from political analysts and followers.

[117][118][119] Although information was limited during his stay in London, he was pictured on 9 March meeting the most senior cleric of the world Anglican congregation, Archbishop of Canterbury Justin Welby.

[126] Some prominent Nigerian figures urged the President to take a long-term medical leave,[127][128] citing his failure to make any public appearances over a two-week period.

Buhari's first tenure as head of state coincided with a decline in oil prices similar to his second stint but his administration has not shown dedicated effort to diversify sources of government spending.

Unemployment levels remain high and any effort to increase non-oil revenues has not improved while government deficit spending include a significant portion of its yearly budget dedicated to service debts.

[150] In May 2018, the Economic and Financial Crimes Commission (EFCC), Nigeria's anti-corruption agency, announced that 603 Nigerian figures had been convicted on corruption charges since Buhari took office in 2015.

[154][155] In July 2020, Ibrahim Magu the EFCC chairman was arrested by the Department of State Services (DSS) over damaging security reports concerning his activities as the Buhari administration's leading anti-corruption figure and alleged financial irregularities, he was later replaced by Mohammed Umar.

[156][157][158][159] In December 2020, Former Pension Reform Taskforce head Abdulrasheed Maina, who was arrested in the neighboring country of Niger after jumping bail, appeared in an Abuja court on a 12-count charge of fraud and money laundering.

[168] Other groups supported by Al-Qaeda in the Islamic Maghreb such as Ansaru, who were driven from Mali due to the French-led Operation Serval have surfaced and co-operated with Boko Haram despite being its rival.

[176] The Middle Belt region of Nigeria has been vulnerable to clashes between farmers and cattle herders, two groups trying to secure arable land for grazing or farming and access to water.

[177] The administration's effort to solve the conflict led to the National Livestock Transformation Plan to modernise cattle grazing and stabilize the Middle Belt region.

[195] Since independence in 1960, the Nigerian Police Force has been at the forefront of tackling organised crime in Nigeria with the recent spate of banditry, cultism, drug trafficking, fraud and kidnapping drastically affecting its personnel capacity,[196] leaving a vacuum for SARS members to exploit and commit extrajudicial killings.

[197] On 13 October Mohammed Adamu the Inspector General of Police announced the creation of a new unit the Special Weapons and Tactics (SWAT) to take over the duties of SARS.

[199] On 14 October, the demonstrations continued with at least ten protestors being killed, and violent clashes occurring between pro-SARS and anti-SARS protesters with the elite Presidential Guard Brigade intervening in the federal capital.

Umaru Dikko, a former Minister of Transportation under the previous civilian administration of President Shagari who fled the country shortly after the coup, was accused of embezzling $1 billion in oil profits.

In 2013, Muhammadu Buhari made a series of statements, when he asked the Federal Government to stop the killing of Boko Haram members and blamed the rise of the terrorist group on the prevalence of Niger Delta militants in the South.

[221] He also questioned the special treatment including close to $500 million a year paid to 30,000 militants under the amnesty programme since 2013[222] by the Federal Government and deplored the fact that Boko Haram members were killed and their houses destroyed.

[228] In September 2016, President Buhari came under heavy criticism after a newspaper report found him using plagiarized speech during the launching of a national re-orientation campaign tagged "Change begins with me".

[231][232] However, one week later, a deputy director in the State House linked to the speech was redeployed and presidency assured Nigerian public that it has taken steps to avoid a repeat of such an embarrassing occurrence by implementing digital tools that detect plagiarism.

In 2015, Buhari declared US$150,000 cash; in addition to five homes and two mud houses as well as farms, an orchard and a ranch of 270 head of cattle, 25 sheep, five horses and a variety of birds, shares in three firms, two undeveloped plots of land, and two cars bought from his savings.