Del Quentin Wilber reports on the Crime Scene blog:

The first witness in the Roger Clemens perjury trial was called Wednesday afternoon as the government called Charles W. Johnson, House parliamentarian from 1994 to 2004.

Johnson is expected to testify about why Congress had the authority to investigate the use of steroids in baseball. Attorneys for both sides presented their opening arguments to the jury earlier Wednesday.

Defense lawyers have signaled that they will argue that Clemens cannot be convicted of obstructing Congress because the House committee overstepped its authority when it held a hearing pitting the pitcher against his trainer.

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