The U.S. Securities and Exchange Commission (SEC) logo adorns an office door at the SEC headquarters in Washington, in this June 24, 2011, file photo. As the U.S. Securities and Exchange Commission ... more 
The U.S. Securities and Exchange Commission (SEC) logo adorns an office door at the SEC headquarters in Washington, in this June 24, 2011, file photo. As the U.S. Securities and Exchange Commission seeks to become a more formidable force in the courtroom, a string of trial defeats in the past six months has exposed a weak spot: witness testimony. In four of the five trials that the securities regulator recently lost, the jury or judge were not convinced by the witnesses brought in by SEC litigators, according to court transcripts, rulings and interviews with defense lawyers. While there were also other factors influencing the verdicts, some legal experts said the issues with witness credibility were significant and reflect the need for SEC litigators to better vet and prepare their witnesses - or drop cases where they aren't strong enough. To match story Insight USA-SEC/COURT REUTERS/Jonathan Ernst/Files (UNITED STATES - Tags: CRIME LAW POLITICS BUSINESS LOGO) less 
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Reuters | Photo By JONATHAN ERNST / REUTERS
Mon, Mar 10, 2014 1:12 AM EDT