The NYPD arrested and jailed nearly 400,000 people for possessing small amounts of marijuana between 1997 and 2007, a tenfold increase in marijuana arrests over the previous decade and a figure marked by startling racial and gender disparities, according to a report released Tuesday at the New York Civil Liberties Union. The report, The Marijuana Arrest Crusade in New York City: Racial Bias in Police Policy 1997-2007, is the first ever in-depth study of misdemeanor marijuana arrests in New York City during the Giuliani and Bloomberg administrations.