Under the Buhari regime military security was the criteria for judicial action, often in the form of military tribunals. The government not only gave the NSO greater powers but also promulgated decrees that directly violated human rights. The most notable were State Security (Detention of Persons) Decree Number 2 of 1984, which empowered the chief of staff at Supreme Headquarters to detain anyone suspected of being a security risk indefinitely without trial (detention was for three months initially, and then renewable), and Decree Number 4, which made the publication of any material considered embarrassing to any government official a punishable offense. Under Decree Number 2, many people considered "enemies" of the government were detained in NSO cells and allegedly tortured. Second Republic government officials, whom the Buhari regime held collectively responsible for the economic mess, were detained without trial or were tried by special military tribunals. At these tribunals, the accused was assumed guilty until proved innocent rather than innocent until proved guilty. Journalists and media organizations were regularly harassed by security agents; organized interest groups whose members dared to criticize the government openly or engage in demonstrations or strikes were proscribed. Under the Buhari administration, the NSO engaged in widespread abuses of due process, including detention without charge and trial, arrests without pretext, and wiretapping. The NSO's performance was bluntly criticized after the 1980 uprisings by the Maitatsine movement. It had penetrated the movement but failed to prevent it from instigating bloody riots. The Maitatsine follow the teachings of Maitatsine Marwa, an Islamic leader from Cameroon whose activities in Nigeria led to his expulsion from Kano in 1960 and a series of bloody uprisings in the 1980's in which more than 4,000 persons are believed to have died.

The Nigeria Police Force (NPF) is designated by Section 194 of the 1979 constitution as the national police with exclusive jurisdiction throughout the country. Constitutional provision also exists, however, for the establishment of separate NPF branches "forming part of the armed forces of the Federation or for their protection of harbours, waterways, railways and airfields." One such branch, the Port Security Police, was reported by different sources to have a strength in 1990 of between 1,500 and 12,000. Nigeria's police began with a thirty-member consular guard formed in Lagos Colony in 1861. In 1879 a 1,200-member armed paramilitary Hausa Constabulary was formed. In 1896 the Lagos Police was established. A similar force, the Niger Coast Constabulary, was formed in Calabar in 1894 under the newly proclaimed Niger Coast Protectorate. Likewise, in the north, the Royal Niger Company set up the Royal Niger Company Constabulary in 1888 with headquarters at Lokoja. When the protectorates of Northern and Southern Nigeria were proclaimed in the early 1900s, part of the Royal Niger Company Constabulary became the Northern Nigeria Police, and part of the Niger Coast Constabulary became the Southern Nigeria Police. Northern and Southern Nigeria were amalgamated in 1914, but their police forces were not merged until 1930, forming the NPF, headquartered in Lagos. During the colonial period, most police were associated with local governments (native authorities). In the 1960s, under the First Republic, these forces were first regionalized and then nationalized. The NPF performed conventional police functions and was responsible for internal security generally; for supporting the prison, immigration, and customs services; and for performing military duties within or outside Nigeria as directed. Plans were announced in mid-1980 to expand the force to 200,000. By 1983, according to the federal budget, the strength of the NPF was almost 152,000, but other sources estimated it to be between 20,000 and 80,000. Reportedly, there were more than 1,300 police stations nationwide. Police officers were not usually armed but were issued weapons when required for specific missions or circumstances. They were often deployed throughout the country, but in 1989 Babangida announced that a larger number of officers would be posted to their native areas to facilitate police- community relations.

The NPF was under the general operational and administrative control of an inspector general appointed by the president and responsible for the maintenance of law and order. He was supported at headquarters in Lagos by a deputy inspector general and in each state by police commissioners. The 1979 constitution provided for a Police Service Commission that was responsible for NPF policy, organization, administration, and finance (except for pensions), In February 1989, Babangida abolished the Police Service Commission and established the Nigeria Police Council in its stead, under direct presidential control. The new council was chaired by the president; the chief of General Staff, the minister of internal affairs, and the police inspector general were members. As part of the government reorganization in September 1990, Alhajji Sumaila Gwarzo, formerly SSS director, was named to the new post of minister of state, police affairs. In late 1986, the NPF was reorganized nationwide into seven area commands, which superseded a command structure corresponding to each of Nigeria's states. Each command was under a commissioner of police and was further divided into police provinces and divisions under local officers. NPF headquarters, which was also an area command, supervised and coordinated the other area commands. The 1986 NPF reorganization was occasioned by a public eruption of tensions between the police and the army. A superintendent was suspended for a time for grumbling that the army had usurped police functions and kept police pay low, and there were fights between police and army officers over border patrol jurisdiction. The armed forces chief of staff announced a thorough reorganization of the NPF into the seven new area commands and five directorates (criminal investigations, logistics, supplies, training, and operations) under deputy inspectors general. About 2,000 constables and 400 senior police officers were dismissed by mid-1987, leaving senior police officers disgruntled. In mid-1989 another NPF reorganization was announced after the AFRC's acceptance of a report by Rear Admiral Murtala Nyako. In 1989 the NPF also created a Quick Intervention Force in each state, separate from the mobile police units, specifically to monitor political events and to quell unrest during the transition to civil rule. Each state unit of between 160 and 400 police was commanded by an assistant superintendent and equipped with vehicles, communications gear, weapons, and crowd control equipment, including cane shields, batons, and tear gas.

The NPF operating budget between 1984 and 1988 remained in the N360 million to N380 million range, and in 1988 increased to N521 million. More notable were large capital expenditure infusions of N206 million in 1986 and N260.3 million in 1988, representing 3.5 and 2.5 percent of total federal capital expenditures in those years. These increases were used to acquire new communications equipment, transport, and weapons to combat the rising crime wave, such as 100 British Leyland DAF Comet trucks delivered in 1990. Despite these purchases, an NPF study in late 1990 concluded that the force's budget must double to meet its needs. Although generally considered an attractive career, the NPF experienced endemic problems with recruiting, training, inefficiency, and indiscipline, and it lacked expertise in specialized fields. Corruption and dishonesty were widespread, engendering a low level of public confidence, failure to report crimes, and tendencies to resort to self-help. Police were more adept at paramilitary operations and the exercise of force than at community service functions or crime prevention, detection, and investigation. During the Obasanjo period, an attempt was made to expand the NPF by reducing the recruitment age from nineteen to seventeen and by enrolling demobilized soldiers, but it failed. In mid-1980 the then federal police minister acknowledged that the police had recovered only 14 percent of the US$900 million worth of property reported stolen in the preceding six months, and that only 20 percent of the 103,000 persons arrested had been found guilty, a performance record about the same as that reported in the 1960s. The use of excessive violence in quelling student disorders led the AFRC in June 1986 to direct the police to use only rubber bullets in containing student riots. Reports of police collusion with criminals were common, as were official appeals to police officers to change their attitude toward the public, to be fair and honest, and to avoid corrupt practices. In an effort to reduce bribery and to make identification of offenders easier, police officers on beats and at checkpoints were not allowed to carry more than N5 on their person.

Drug-related crime emerged as a major problem in the 1980s. At least 328 cocaine seizures were made between 1986 and 1989, and the number of hard drug convictions surged from 8 in 1986 to 149 in 1989, with women accounting for 27 percent of the 275 total convictions during this period. Drug-induced psychoses accounted for 15 percent of admissions to four psychiatric hospitals in l988. In a related development, the federal Ministry of Health reported in 1989 that about one-half of the drugs available in Nigeria were imitations, leading to a series of counterfeit and fake drugs decrees imposing increasingly higher penalties for violations. The Government of Nigeria (GON) counter-narcotics programs have failed to materialize or have been ineffective. Efforts by the Nigerian Drug Law Enforcement Agency (NDLEA) have been hindered by widespread corruption in law enforcement and other agencies and by the lack of clear policy guidance and substantive government support. Counter-narcotics legislation has been enacted, but has produced no prosecutions or convictions of major drug traffickers. Decree Number 48 of January l990 established a National Drug Law Enforcement Agency to eliminate the growing, processing, manufacturing, selling, exporting, and trafficking of hard drugs, and the decree prescribed stiffer penalties for convicted offenders. Although Babangida had abolished the death penalty for convicted drug dealers, by the end of the decade there were public calls to restore it. Stricter security measures were introduced at Lagos International Airport in 1989 to curb a crime wave there, and a plan was instituted in August 1989 to control black market activities. The NDLEA maintains a presence at international airports, making regular seizures of heroin from individual couriers, and conducts raids at seaports and border checkpoints. Efforts to eradicate cannabis cultivation focused on the destruction of isolated plantings. The NDLEA has attempted to shift the focus of operations from the arrest of couriers to the prosecution of controlling members of narcotics and money laundering organizations. However, these nascent efforts are stymied by endemic corruption in other government agencies as well as lack of support, funding and skill.

The State Security (Detention of Persons) Decree of 1984 (Decree Two) allows the Government to detain without charge persons suspected of acts prejudicial to state security or harmful to the economic well-being of the country. When invoked, Decree Two suspends the detainee's civil liberties and precludes judicial review. Many citizens consider Decree Two to be the main threat to their basic freedoms, because the judicial ouster clause encourages arbitrary detention and fails to define what constitutes acts under the Decree's purview. Decree 11 of 1994 authorizes the PRC Vice Chairman or the Commissioner of Police to detain persons for up to 3 months without charge.

Decree 12 states that "no act of the federal military Government may henceforth be questioned in a court of law" and "divests all courts of jurisdiction in all matters concerning the authority of the federal Government."

In June 1996, in response to the report of a UN fact-finding team sent to investigate human rights and the transition process, the Government announced the repeal of Decree 14 of 1994, which had effectively suspended the right of habeas corpus by forbidding courts from hearing cases demanding that the Government produce in court those detained under Decree Two. However, despite this repeal, the Government still retains full legal authority under Decree Two and Decree 12 of 1994 to detain citizens arbitrarily and dispense with habeas corpus challenges, and the Government regularly defied court orders to produce detainees.

In June 1996 the Government also amended the Civil Disturbances (Special Tribunal) Decree of 1987 to remove members of the armed forces from the membership of the tribunal and allow for a right of appeal to the Special Appeals Tribunal. Military personnel convicted of coup plotting do not, however, enjoy the right of appeal to the Special Appeals Tribunal, and the decree remained silent regarding appeals for civilians convicted of coup plotting, but all indications are that the decree does not apply to them.