Question: The Derry Citizen's Defense Association was organized in response to which police force known as the most dangerous police force in the world?

Context paragraphs:
National Police of Colombia: The National Police of Colombia (Spanish: "Policía Nacional de Colombia") is the national police force of Colombia.  Although the National Police is not part of the Military Forces of Colombia (Army, Navy, and Air Force), it constitutes along with them the "Public Force" and is also controlled by the Ministry of Defense.  Unlike many nations which use a tiered system of law enforcement, the National Police is the only civilian police force in Colombia.  The force's official functions are to protect the Colombian nation, enforce the law by constitutional mandate, maintain and guarantee the necessary conditions for public freedoms and rights and to ensure peaceful cohabitation among the population.

San Juan Police Department: The "Policia Municipal de San Juan" (San Juan Municipal Police or San Juan Police Department, in English) is the main police force for the city of San Juan, Puerto Rico, with jurisdiction only on the city limits of San Juan.  It is also the largest city police force in Puerto Rico, and the second largest police force in the island after of the Puerto Rico Police Department.  It was created in 1977 under law #19 of May 12, 1977, known as "Ley de la Policia Municipal" (Municipal Police Law) creating local police forces in each city of Puerto Rico .

Kochi City Police: Kochi City Police (KCP) is the police force of the Indian city of Kochi.  The force is headed by a Police Commissioner, an IPS officer.  The city police was reorganized as Metro Police force, on 1 April 1966, after forming City Corporation of Cochin.  Kochi City Police is one of the most advanced police force, considering the strategic importance of the city.  The Kochi City police teamed up with Vodafone India, for dedicated mobile communications support.

Carolina Police Department: The Carolina Police Department or Policia Municipal de Carolina is the main police force for the city of Carolina, Puerto Rico.  It was created under law #19 of May 12, 1977, known as "Ley de la Policia Municipal" (Municipal Police Law) creating the local police forces in each city of Puerto Rico.  It was one of the first municipal police forces in Puerto Rico.  Between late 1980 and late 2009, the department has become one of the fewest municipal police force in Puerto Rico with the largest number of officers, equipment and budget.  Since former mayor Jose Aponte de la Torre took office from 1988 unit his death in 2005, the police force has equipped with equipment, such as patrols equipped with weapons and cage, criminal information system and tactical bulletproof vests for its officers.

Royal Ulster Constabulary: The Royal Ulster Constabulary was the police force in Northern Ireland from 1922 to 2001.  Following the awarding of the George Cross in 2000, its formal title became the Royal Ulster Constabulary, GC.  It was founded on 1 June 1922 as a successor to the Royal Irish Constabulary (RIC).  At its peak the force had around 8,500 officers with a further 4,500 who were members of the RUC Reserve.  During the Troubles, 319 members of the RUC were killed and almost 9,000 injured in paramilitary assassinations or attacks, mostly by the Provisional IRA, which made, by 1983, the RUC the most dangerous police force in the world in which to serve.  In the same period, the RUC killed 55 people, 28 of whom were civilians.

Derry Citizens' Defence Association: The Derry Citizens' Defense Association (DCDA) was an organisation set up in Derry in July 1969 in response to a threat to nationalist residents from the Royal Ulster Constabulary (RUC) and civilian unionists, in connection with the annual parade of the Apprentice Boys of Derry on 12 August.  This followed clashes with the RUC in January and April 1969, which resulted in widespread violence.  The DCDA played a prominent role in co-ordinating the area's residents in the Battle of the Bogside, and was the effective government of the self-declared Free Derry from August to October 1969.  Its leaders included Seán Keenan, Paddy Doherty and Johnnie White.  Keenan and White were well-known republicans.

Royal Irish Constabulary: The Royal Irish Constabulary (RIC, Irish: "Constáblacht Ríoga na hÉireann"; simply called the Irish Constabulary 1836–67) was the police force in Ireland from the early nineteenth century until 1922.  A separate civic police force, the unarmed Dublin Metropolitan Police controlled the capital, and the cities of Derry and Belfast, originally with their own police forces, later had special divisions within the RIC.  About seventy-five percent of the RIC were Roman Catholic and about twenty-five percent were of various Protestant denominations, the Catholics mainly constables and the Protestants officers.  The RIC's successful system of policing influenced the armed Canadian North-West Mounted Police (predecessor of the Royal Canadian Mounted Police), the armed Victoria Police force in Australia, and the armed Royal Newfoundland Constabulary in Newfoundland.  In consequence of the Anglo-Irish Treaty, the RIC was disbanded in 1922 and was replaced by the Garda Síochána in the Irish Free State and the Royal Ulster Constabulary in Northern Ireland.

List of Commissioners of New South Wales Police: The Commissioner of the New South Wales Police Force (Known from 1851 to 1926 as the Inspector-General of the New South Wales Police Force) is the head of New South Wales's Police Force.  The post is currently held by Mick Fuller, who replaced Andrew Scipione on 31 March 2017.  The rank is usually referred to as the New South Wales Police Commissioner or simply just "Commissioner".  The New South Wales Police Force has had 22 Commissioners since 1851.

Seoul Metropolitan Police Agency: The Seoul Metropolitan Police Agency (SMPA; Hangul: Korean: 서울지방경찰청 ; ; Hanja: 서울地方警察廳 ) is the primary police force for the South Korean capital city of Seoul; it is not an independent police force in of itself, but is one of 16 provincial sub-divisions of the National Police Agency.  The SMPA is headquartered along with the National Police Headquarters in Seoul itself.  While modern police agencies of Seoul can trace their history back to 1945 with the creation of a Korean police force, the modern-day Metropolitan Police Agency in Seoul came into being on August 1, 1991 and currently polices over 10 million inhabitants.

Special police: Special police (also see auxiliary police) usually describes a police force or unit within a police force whose duties and responsibilities are significantly different from other forces in the same country or from other police in the same force, although there is no consistent international definition.  A special constable, in most cases, is not a member of a special police force; in countries in the Commonwealth of Nations and often elsewhere, a special constable is a voluntary or part-time member of a national or local police force or a person involved in law enforcement who is not a police officer but has some of the powers of a police officer.

Supporting paragraphs: Derry Citizens' Defence Association Royal Ulster Constabulary
Answer: Royal Ulster Constabulary