NEW YORK (CBSNewYork/AP) — Ten Metropolitan Transportation Authority workers have been charged with falsifying subway signal inspection reports in a long-running fraud investigation.

Prosecutors said eight signal maintainers were charged Monday with tampering with public records. Two of their supervisors were charged Friday with record tampering and official misconduct. All have pleaded not guilty.

WCBS 880’s Paul Murnane reports

Authorities say that between January 2009 and December 2010, the signal maintainers made at least 33 fake entries in inspection logbooks.

“Our subway system is one of the oldest and most expansive in the world, and it takes significant effort to maintain it,” Manhattan District Attorney Cyrus Vance said in a statement. “No matter how lax an agency’s internal controls might be, tampering with public records to cover up a failure to inspect signal equipment is never acceptable conduct.”

One of the supervisors is accused of urging some maintainers to record a greater number of fake entries while the other is accused of failing to make sure that inspections were performed.

“They were ordered to meet quotas that some might describe as impossible,” said Arthur Schwartz, an attorney representing six of the defendants.

“This whole problem was right from the top of the MTA,” said John Churello with the Transit Workers Union. “The signal managers at the time condoned this behavior and put pressure on our guys.”

But the MTA disputes that claim, saying: “The union is flat-out wrong to say that management pressure for high performance standards forced employees to break the law.”

MTA officials say they have taken a number of actions to address the problems cited in the investigation.

(TM and Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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