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Petra Diamonds: Mistreatment of Artisanal Miners Leading to Litigation and a Financial and Structural Settlement Agreement

The Williamson Mine, operated by Petra Diamonds, is a large diamond mine in Tanzania. Due to a history of artisanal mining in the area, and a lack of employment opportunities in the area, the Williamson Mine frequently deals with illegal mining. Allegedly, the mine’s security personnel have dealt with artisanal miners in an aggressive and cruel manner, including shootings, stabbings, beatings, and cruel and inhumane treatment of detainees. In response, 71 anonymous Tanzanians filed suit against Petra Diamonds in the London High Court, alleging violation of human rights, injuries, and deaths at the hands of the private security personnel. The parties settled about a year later, with the settlement involving a financial payout, various community projects, and a new grievance mechanism.

Keywords: clash with locals, poor training, inhumane treatment, extractive industry, weapons


The Williamson Mine is one of the world’s longest continuous mining operations, beginning in the 1940s under British colonial rule. Petra Diamonds owns the mine through a 75% stake in the local operating company, and the Tanzanian government holds the remaining 25%.

The Williamson Mine is located in a rural area of the Kishapu District of northern Tanzania’s Shinyanga region. Within the eleven neighbouring communities of the mine, there is an estimated population of a little over 30,000 residents.

Small-scale (artisanal) diamond mining in the Shinyanga region has been practised since at least the early twentieth century. Some local residents seek to supplement their incomes by searching for diamonds in the nearby mines. A 2009 World Bank report found that for the “vast majority” of local residents engaged in artisanal mining around the Williamson Mine, it is “a poverty driven coping mechanism undertaken due to the lack of viable alternative livelihood options.”

A 2011 study commissioned by Tanzania’s Ministry of Energy and Minerals found that 86% of employment opportunities for Tanzanians at the Williamson Mine did not go to local people, and those positions tended to involve casual, short-term labour.

Generally, the mineral wealth of the region has made it a target for illegal mining operations. In response, Petra Diamond has asserted that its control of the mine and its diamonds is “non-negotiable – and we will employ all necessary means – over and covert – to protect our diamonds from theft or loss.”

The Williamson Mine employs a Tanzanian private security contractor, Zenith Security Services, to guard the site. The security personnel are deployed with firearms, tear-gas, batons, and other weapons.

The Incident 

In November 2020, a UK-based NGO, RAID, reported on various alleged human rights abuses at the Petra Diamonds-owned Williamson diamond mine. Based on field research of the mine, RAID found evidence that since Petra Diamonds acquired the mine, there had allegedly been seven killings, forty-one assaults, detainment and incarceration in poor conditions, deprivation of food and medical treatment, and beatings.

In some incidents, the assaults appeared to amount to torture and/or inhuman and degrading treatment. Some individuals alleged severe beatings, with pain being intentionally inflicted on the detainees. Individuals also alleged the purposeful denial of food, water, medical care, and guards disallowing individuals to get up and move, sometimes even being handcuffed to hospital beds at the medical centre.

After the original report, further research by RAID revealed that security guards allegedly swapped rubber projectiles with metal shot in their weapons to intimidate trespassers, increasing the risk of serious injury or death.

Zenith guards were allegedly directly implicated in nearly all killings and abuses documented; these guards are readily identifiable due to their uniforms and weapons. RAID found only two cases in which security guards were charged or convicted by authorities for human rights abuses. One security guard was sentenced to six months’ conditional discharge for allegedly shooting two local residents detained on the mine site, and the other was allegedly sentenced to two years in prison for killing a local resident.

Some injured detainees were taken to Williamson Diamonds Hospital, the mine-owned and operated medical facility. The interviewed individuals described the hospital staff as ignoring and/or providing substandard care to those brought in by security personnel.

Legal Aspects

Court cases

In May 2020, 32 Tanzanian nationals brought a lawsuit to the London High Court. The number of claimants expanded to 72 in November 2020. Ten of the claims were brought by families of those who are alleged to have been killed at the Williamson Mine. The claimants alleged breaches of human rights, personal injuries, and deaths arising from the mine’s security operations.

The International Code of Conduct

The International Code of Conduct requires that Personnel of Member and Affiliate companies take all reasonable steps to avoid the use of force, and if force is used, it should be proportionate to the threat and appropriate to the situation. (Rules for the Use of Force : paragraph 29, Use of Force : paragraph 30-32)

Resources on Use of Force

Additionally, security personnel are only allowed to apprehend persons to defend themselves or others against an imminent threat of violence following an attack or crime against Company Personnel, clients, or property under their protection. Apprehension and detention must be consistent with international and national law, and all apprehended and detained persons must be treated humanely and consistent with their status and protections under applicable human rights law and international humanitarian law. (Detention: paragraph 33)

Resources on Apprehending Persons

Resources on Detention

Further, the International Code of Conduct requires stringent selection and vetting of personnel, assessment of performance and duties (paragraphs 45 to 49), and training of personnel of the Code and relevant international law, including human rights and international criminal law (paragraph 55). Meeting the requirements of the Code of Conduct, can help private security companies and their clients ensure that private security personnel are qualified, trained, supported, informed, and responsible.

Meeting the requirements of the Code of Conduct can help private security companies and their clients ensure that private security personnel are qualified, trained, supported, informed, and responsible.


Public Relations

After Petra Diamonds settled with the Tanzanian national claimants, the company released a press release to the market. Petra Diamonds stated that it had “acted decisively to hold individuals to account” and that disciplinary action had been taken with several employees having left (or would be leaving) the company. Petra Diamonds said it had appointed a new security contractor, and closed the on-site detention facility.

Petra Diamonds also acknowledged that “past incidents have taken place that regrettably resulted in the loss of life, injury, and mistreatment of illegal diggers.”

Settlements and Fines

In May 2021, Petra Diamonds reached a settlement, not admitting any liability, with the 71 anonymous claimants. Petra Diamonds agreed to pay 4.3 million sterling pounds ($6 million) in the settlement.

The settlement also included the establishment of an “operational grievance mechanism” to track human rights abuses at Williamson Mine, and Petra Diamonds’ involvement in community projects for three years.

The community projects included enhanced community medical support, access to the concession to collect firewood and livestock, and a gender-based violence campaign to provide support and counselling for victims.

As part of the settlement, a substantive framework for the valuation of twenty-five additional claims was agreed to between the parties.

The Companies also agreed to embed a non-harassment and victimisation policy to safeguard victims and human rights defenders against future harm or intimidation.


How can private security companies and their personnel avoid conflicts with small-scale miners who might enter a mining client’s land?

What are the challenges of preventing cruel and inhuman treatment in client-owned detention and medical centres, and how can these challenges be addressed?

Related incidents




Case prepared by Madison Zeeman

Descargo de responsabilidad

De acuerdo con la cláusula de exención de responsabilidad de la página de inicio, ni la Asociación del Código de Conducta Internacional ni ninguno de los autores pueden identificarse con las opiniones expresadas en el texto o las fuentes incluidas en «Defender la Seguridad Responsable: El Mapa de Casos del Código Internacional de Conducta».