Article | Journal of Financial Economics | December 2013

Legislating Stock Prices

by Lauren Cohen, Karl Diether and Christopher Malloy


We demonstrate that legislation has a simple, yet previously undetected impact on stock prices. Exploiting the voting record of legislators whose constituents are the affected industries, we show that the votes of these "interested" legislators capture important information seemingly ignored by the market. A long-short portfolio based on these legislators' views earns abnormal returns of over 90 basis points per month following the passage of legislation. Industries that we classify as beneficiaries of legislation experience significantly more positive earnings surprises and positive analyst revisions in the months following passage of the bill, as well as significantly higher future sales and profitability. We show that the more complex the legislation, the more difficulty the market has in assessing the impact of these bills; further, the more concentrated the legislator's interest in the industry, the more informative are her votes for future returns.

Keywords: legislator incentives; voting; Return Predictability; lobbying; Motivation and Incentives; Government Legislation; Stocks;


Cohen, Lauren, Karl Diether, and Christopher Malloy. "Legislating Stock Prices." Journal of Financial Economics 110, no. 3 (December 2013): 574–595. (Winner of Fama-DFA Prize for the Best Paper Published in the Journal of Financial Economics in Asset Pricing (Distinguished Paper) 2013.)