Executives from the bailed-out Wall Street giant Goldman Sachs are appearing before a Senate hearing today amidst increasing scrutiny on their practices. On Monday, the Senate Permanent Subcommittee on Investigations said Goldman’s alleged unlawful activities extended beyond the single mortgage-related securities case that led to civil fraud charges earlier this month. Subcommittee chair Senator Carl Levin of Michigan held up copies of emails he says prove Goldman devised not just one but a number of complex deals that resulted in $3.7 billion in earnings for the company. Investigators say Goldman’s tactics centered around making negative bets, or shorts, that profited from the housing market’s collapse.