The IPCC was established in 1988 to specifically investigate 'human induced' climate change. It is therefore no surprise that it found evidence for Anthropogenic Global Warming.
ROLE
2. The role of the IPCC is to assess on a comprehensive, objective, open and transparent basis the scientific, technical and socio-economic information relevant to understanding the scientific basis of risk of human-induced climate change, its potential impacts and options for adaptation and mitigation. IPCC reports should be neutral with respect to policy, although they may need to deal objectively with scientific, technical and socio-economic factors relevant to the application of particular policies.
(PRINCIPLES GOVERNING IPCC WORK, 1998)
It also had a clear political remit (albeit paying lip service to neutrality) and actively involved governments in its published assessments.
3. Review is an essential part of the IPCC process. Since the IPCC is an intergovernmental body, review of IPCC documents should involve both peer review by experts and review by governments.
(PRINCIPLES GOVERNING IPCC WORK, 1998)
This has led to the Global Warming juggernaut being harnessed for political ends:
“one must say clearly that we redistribute de facto the world’s wealth by climate policy….This has almost nothing to do with environmental policy anymore.”
IPCC official Ottmar Edenhofer, November 2010
"This is the first time in the history of mankind that we are setting ourselves the task of intentionally, within a defined period of time, to change the economic development model that has been reigning for at least 150 years, since the Industrial Revolution,"
Executive Secretary of UNFCCC, Christiana Figueres, 3rd February 2015.