Houston ? Arthur Andersen LLP pleaded innocent Wednesday to criminal charges that it obstructed justice by shredding tons of documents and deleting computer files related to Enron.

The hearing was the auditing firm’s first since a federal indictment was unsealed last week.

Outside the courthouse, hundreds of chanting Arthur Andersen employees protested the indictment, saying they aren’t cowering from the charges.

“I was not involved in Enron and I bet you couldn’t find six people here who were,” said Charlotte Williams, who has worked at Arthur Andersen for 21 years. “We’re going to stay until the lights go out if necessary.”

U.S. District Judge Melinda Harmon, who ultimately will hear the case, set a trial date of May 6 and said she hoped to complete the trial in three weeks.

Rusty Hardin, an Andersen attorney, had said the company wanted a swift jury trial to challenge what he called flimsy government evidence.

The indictment, the first related to Enron Corp.’s collapse, accuses Andersen of obstructing justice by shredding tons of documents and deleting computer files related to Enron audits.