Law Commons^™

Power And Statistical Significance In Securities Fraud Litigation, Jill E. Fisch, Jonah B. Gelbach

All Faculty Scholarship

Event studies, a half-century-old approach to measuring the effect of events on stock prices, are now ubiquitous in securities fraud litigation. In determining whether the event study demonstrates a price effect, expert witnesses typically base their conclusion on whether the results are statistically significant at the 95% confidence level, a threshold that is drawn from the academic literature. As a positive matter, this represents a disconnect with legal standards of proof. As a normative matter, it may reduce enforcement of fraud claims because litigation event studies typically involve quite low statistical power even for large-scale frauds.

This paper, written for …

The Logic And Limits Of Event Studies In Securities Fraud Litigation, Jill E. Fisch, Jonah B. Gelbach, Jonathan Klick

All Faculty Scholarship

Event studies have become increasingly important in securities fraud litigation after the Supreme Court’s decision in Halliburton II. Litigants have used event study methodology, which empirically analyzes the relationship between the disclosure of corporate information and the issuer’s stock price, to provide evidence in the evaluation of key elements of federal securities fraud, including materiality, reliance, causation, and damages. As the use of event studies grows and they increasingly serve a gatekeeping function in determining whether litigation will proceed beyond a preliminary stage, it will be critical for courts to use them correctly.

This Article explores an array of …

Chevron, Greenwashing, And The Myth Of 'Green Oil Companies', Miriam A. Cherry, Judd F. Sneirson

All Faculty Scholarship

As green business practices grow in popularity, so does the temptation to “greenwash” one’s business to appear more environmentally and socially responsible than it actually is. We examined this phenomenon in an earlier paper, using BP and the Deepwater Horizon catastrophe as a case study and developing a framework for policing dubious claims of corporate social responsibility. This Article revisits these issues focusing on Chevron, an oil company that claims in its advertisements to care deeply about the environment and the communities in which it operates, even as it faces an $18 billion judgment for polluting the Ecuadorean Amazon and …

Significant Statistics: The Unwitting Policy Making Of Mathematically Ignorant Judges, Michael I. Meyerson, William Meyerson

All Faculty Scholarship

This article will explore several areas in which judges, hampered by their mathematical ignorance, have permitted numerical analysis to subvert the goals of our legal system. In Part II, I will examine the perversion of the presumption of innocence in paternity cases, where courts make the counter-factual assumption that regardless of the evidence, prior to DNA testing, a suspect has a 50/50 chance of being the father. In Part III, I will explore the unnecessary injection of race into trials involving the statistics of DNA matching, even when race is entirely irrelevant to the particular case. Next, in Part IV, …

Aligning Incentives With Equity: Employee Stock Options And Rule 10b-5, Matthew T. Bodie

All Faculty Scholarship

When the Internet boom was in full swing and the stock markets skyrocketed to new levels, companies new and old used stock options to attract and retain employees. Implicit in those options was the promise that employees could participate in the growth of a company's value. However, as the scandals involving WorldCom, Enron, and Global Crossing demonstrate, corporate managers were not always honest with employees or public investors about the company's true value. Public investors can seek civil remedies for securities fraud through a private action under the Securities and Exchange Commission's Rule 10b-5. The Rule's purchase or sale requirement, …

Securities Fraud In Cyberspace: Reaching The Outer Limits Of The Federal Securities Laws, Constance Z. Wagner

All Faculty Scholarship

This article discusses the increasing use of the Internet for securities transactions, the growth of securitiesfraud perpetrated through that medium and the Securities and Exchange Commission (“SEC”) enforcement program initiated to combat it. The author critiques the position taken by the SEC that the existing anti-fraudprovisions of the federal securities laws can be stretched to cover Internet fraud. Using an enforcement action brought by the SEC against an online stock trading guru named Tokyo Joe as an example of the confused jurisprudence that results when pre-cyberspace law is applied to securities fraud in cyberspace, the author proposes a different regulatory …