Operation Cat Drop is the name commonly given to an account, of uncertain veracity, about the delivery, by the United Kingdom's Royal Air Force, of cats to a remote village in Sarawak, Borneo.
 The cats were delivered in crates, dropped by parachute, as part of a broader program of supplying cats to combat a plague of rats.
 The cat population had previously been reduced as an unintended consequence of spraying DDT for malaria control.
 The story, often with various elaborations is often told as an illustration of the problems that may arise from well-intended interventions in the environment, or of unintended consequences more generally.
A slippery slope argument (SSA), in logic, critical thinking, political rhetoric, and caselaw, is a consequentialist logical device in which a party asserts that a relatively small first step leads to a chain of related events culminating in some significant (usually negative) effect.
 The core of the slippery slope argument is that a specific decision under debate is likely to result in unintended consequences.
 The strength of such an argument depends on the warrant, i.e. whether or not one can demonstrate a process that leads to the significant effect.
 This type of argument is sometimes used as a form of fear mongering, in which the probable consequences of a given action are exaggerated in an attempt to scare the audience.
 The fallacious sense of "slippery slope" is often used synonymously with continuum fallacy, in that it ignores the possibility of middle ground and assumes a discrete transition from category A to category B.
 In a non-fallacious sense, including use as a legal principle, a middle-ground possibility is acknowledged, and reasoning is provided for the likelihood of the predicted outcome.
Steven George Mandis (born in 1970) is an American investor and the founder of Kalamata Capital.
 He is also adjunct associate professor in finance and economics at Columbia University Business School, having previously worked at Goldman Sachs and Citigroup and as a senior advisor to McKinsey.
 He is the author of "What Happened to Goldman Sachs: An Insider's Story of Organizational Drift and its Unintended Consequences" and "The Real Madrid Way: How Values Created the Most Successful Sports Team on the Planet."
Robert King Merton (born Meyer Robert Schkolnick; 4 July 1910 – 23 February 2003) was an American sociologist.
 He spent most of his career teaching at Columbia University, where he attained the rank of University Professor.
 In 1994 he was awarded the National Medal of Science for his contributions to the field and for having founded the sociology of science.
 He is considered a founding father of modern sociology.
Blowback is a term originating from within the American Intelligence community, denoting the unintended consequences, unwanted side-effects, or suffered repercussions of a covert operation that fall back on those responsible for the aforementioned operations.
Christopher Ategeka (born July 10, 1984) is a serial entrepreneur and an engineer in Silicon Valley.
 He pioneered the unintended consequences of technology (UCOT) movement.
 Chris coined and popularized the term "UCOT" in the tech sector and the concept of "UCOT" evangelism.
 He is the founder at LyfBase a solutions company for the negative unintended consequences of technology.
 Before that, he founded Health Access Corps and co-founder of Privail.
Therapeutic jurisprudence ("TJ") studies law as a social force (or agent) which inevitably gives rise to unintended consequences, which may be either beneficial (therapeutic) or harmful (anti-therapeutic).
 These consequences flow from the operation of legal rules or legal procedures - or from the behavior of legal actors (such as lawyers and judges).
 TJ researchers and practitioners typically make use of social science methods and data to study the extent to which a legal rule or practice affects the psychological well-being of the people it affects, and then explore ways in which anti-therapeutic consequences can be reduced, and therapeutic consequences enhanced, without breaching due process requirements.
The Osborne effect is a term referring to the unintended consequences of a company announcing a future product, unaware of the risks involved or when the timing is misjudged, which ends up having a negative impact on the sales of the current product.
 This is often the case when a product is announced too long before its actual availability.
 This has the immediate effect of customers canceling or deferring orders for the current product, knowing that it will soon be obsolete, and any unexpected delays often means the new product comes to be perceived as vaporware, damaging the company's credibility and profitability.
In the social sciences, unintended consequences (sometimes unanticipated consequences or unforeseen consequences) are outcomes that are not the ones foreseen and intended by a purposeful action.
 The term was popularised in the twentieth century by American sociologist Robert K. Merton.
Stephanos Bibas (born 1969) is a professor of law and criminology at the University of Pennsylvania Law School; he is a leading scholar of criminal procedure with expertise in criminal charging, plea bargaining and sentencing.
 He has been announced as a nominee to be a United States Circuit Judge of the United States Court of Appeals for the Third Circuit.
 A former federal prosecutor, Bibas examines how procedural rules written for jury trials have unintended consequences when cases involving jury trials are the exception, rather than the rule, with 95 percent of defendants pleading guilty.
 Bibas also studies the role of substantive goals such as remorse and apology in criminal procedure.

Question: At which University did the sociologist who popularised the term "Unintended consequences" spend most of his career and attain the rank of University Professor?
Answer: at Columbia University