...[M]ore than 200 law and economics professors sent a letter to Congress attacking the investor-state dispute settlement mechanism of the yet-to-be-ratified, 12-country agreement.There’s a distinctly alarmist undertone to their concerns, premised on the notion that rapacious corporations and their lawyers will run roughshod over government regulations intended to protect the environment, health and safety and the rights of workers...Their key concern: investor-state arbitration creates a “parallel and privileged set of legal rights and recourse for foreign economic actors,” according to the letter, which was signed by professors including Harvard Law School’s Laurence Tribe and George Washington University School of Law’s Alan Morrison, who founded Public Citizen Litigation Group. Massachusetts Senator Elizabeth Warren is lending her voice as well.  “This provision empowers companies to challenge laws and regulations they don’t like, with friendly corporate lawyers instead of judges deciding their disputes,” she said during a conference call with reporters on Wednesday...Investor-state arbitration agreements are not new.  They’ve been included in 3,000 investment treaties around the world over the past 50 years, including the North American Free Trade Agreement. But there’s been a sharp uptick in cases in recent years--2015 marked an all-time high, with 70 new cases launched, according to the United Nations Conference on Trade and Development...