Nothing is known of the parentage, tribal affiliation or early life of the Māori policeman Karira, also known as Creed. He first came to notice in 1852 when Donald McLean negotiated with him on behalf of the government to buy Māori-owned land near New Plymouth, on the northern flanks of Mt Taranaki. He was subsequently recruited as the third Māori member of Inspector George Cooper's New Plymouth detachment of the New Ulster Armed Police Force. The Māori constables, of significant tribal standing, were valued for their specialist knowledge and their ability to mediate between Māori and Pākehā.
The settlement's small policing unit had been established in 1846 by McLean, then a police inspector. Many of the region's European population resented being subject to control by a force which included Māori constables. With the establishment of provincial government in October 1853, settlers took control of policing. Their political leaders secured a new arrangement which the general government agreed to as the only way it could retain Māori policing expertise in the province: the Māori constables would be separated from the New Plymouth Province Armed Police Force to constitute a Native Police (partly provincially funded) which could coerce only Māori and mixed-race people. This hybrid force was, in theory, controlled by the general government, with Cooper as its inspector; in practice, it was under provincial direction.
Karira was frequently engaged in inter-racial 'troubleshooting' and state land purchase manoeuvres, as well as policing Māori in and around New Plymouth. In late 1856 the provincial government withdrew its funding of the now two-man Native Police Force, and in the ensuing negotiations for full control by the general government Private Karira resigned on 1 December in protest over impending new conditions – a pay cut, and violation of an understanding that the Native Police Force did not have to undertake regular night duty.
The new head of the force, Inspector Henry Halse, argued strenuously for a restoration of previous pay and conditions, noting that (unlike the European police) the Māori constables had to buy their own uniforms, and frequently travelled far from New Plymouth. Indeed, their duties were 'of a much more important nature in this peculiarly circumstanced Province…than the ordinary duties of the European Constabulary.' After Halse had got his way he persuaded Karira to rejoin the Native Police Force from 1 January 1857.
The Māori police were seldom appreciated by the Pākehā of the province, and not at all by 'insurrectionist' tribes and hapū, particularly after the outbreak of war in 1860. At toll-gates erected by 'rebels', it was Māori police who had to pay the stiffest charges of all, at £500, some six times their annual salary. But the state was appreciative, calling them in, for example, when the soldiery's behaviour provoked altercations with 'friendly' Māori. On 3 January 1863 Constable Karira gained an additional appointment to the Native Land Court in Taranaki, and in April 1864 he was promoted to the position of sergeant in charge of the Taranaki Native Police Force.
During the wars, with much of the countryside in 'rebel' hands, the Native Police Force had fallen again to a two-man force; but with the expansion of Pākehā-settled territory the unit doubled in size. When the Taranaki Provincial Police suffered severe retrenchment early in 1867, an even greater policing burden was thrown on the Māori constables; this included handling Pākehā offenders, who often resisted. On one such occasion Karira and one of his men apprehended a drunken soldier breaking windows; Karira was attacked with a bottle while escorting the soldier to the custody of the Pākehā police.
In September 1867 Sergeant Karira, worn out after years of dedicated service to the state, fought a week-long battle against measles at his home on Devon Line, in suburban Te Henui, New Plymouth. Although he had straddled two worlds, he had not become fully 'Europeanised'. On his deathbed he attributed his impending fate to having violated a tapu by smoking a pipe while burying the bones of his ancestors. A reptile-shaped devil, or ngārara, he averred, had fastened onto his throat and would not let him go until he died.