Stevens prosecutor removed from another case

updated 4:18 p.m. ET June 18, 2009

WASHINGTON - A top Justice Department attorney under criminal investigation for withholding evidence in the case against former Sen. Ted Stevens has been removed as the supervisor of another congressional corruption trial.

Justice spokeswoman Laura Sweeney said William Welch remains head of the department's Public Integrity Section but will no longer oversee the prosecution of former lobbyist Kevin Ring.

Ring is a former associate of imprisoned lobbyist Jack Abramoff and is scheduled to go on trial in September on charges of bribing public officials and obstructing justice.

More than a dozen other Abramoff associates and public officials have been convicted in the probe, most through guilty pleas. Ring is fighting the accusations of wrongdoing.

Welch and four other federal prosecutors are under investigation for withholding evidence from defense attorneys in the Stevens trial.

Stevens served 40 years in the U.S. Senate but lost re-election last fall days after being convicted on corruption charges. The guilty verdict was dismissed in April after the Justice Department acknowledged it had improperly withheld evidence.

Video   Judge tosses charges against Sen. Stevens April 7: Former Alaska Sen. Ted Stevens' corruption conviction was thrown out by a judge, who also ordered a investigation into whether the prosecutors who worked on the case intentionally withheld critical evidence. Nightly News

Sweeney would not comment on whether Welch has been removed from any other cases, but said Welch deputy Raymond Hulser has replaced him as acting chief of the Public Integrity Section in the Ring case only.

The judge who is scheduled to oversee the Ring trial said she wanted Welch off the case. U.S. District Judge Ellen Huvelle told prosecutors at a hearing in April that they should "have a wall" keeping Welch from being involved because of a potential conflict.

Welch's criminal investigation is being led by Washington attorney Henry Schuelke, who is expected to be a witness in Ring's case. The lobbying firm that Abramoff and Ring worked for, Greenberg Traurig, hired Schuelke to conduct an internal investigation after Abramoff was accused of corruption. Ring is charged with two counts of obstruction of justice for lying to Schuelke as part of his investigation.