(The top of this post was updated at 1:45 p.m. ET with news of the prison sentence, and at 3 p.m. ET with the U.S. Attorney's reaction.)

A federal judge in West Virginia has sentenced Hughie Stover to three years in prison. Stover is the former security chief of the Upper Big Branch mine, where 29 miners died in a massive explosion in 2010.

U.S. District Judge Irene Berger stayed within federal sentencing guidelines and ignored federal prosecutors, who sought a 25-year prison term. Stover was convicted in October of lying to investigators and attempting to destroy evidence during the federal criminal investigation of the nation's worst mine disaster in 40 years.

Ken Ward of the Charleston Gazette was in the courtroom in Beckley, W. Va., and he reports that Judge Berger "rebuffed prosecutors" and their call for a 25-year sentence. Stover is 60 and his attorney called the 25-year jail term "a defacto life sentence."

"It is a very serious thing to hang death on anyone, and it should only be done when there is evidence to support it," Berger said in court, according to Ward.

"This represents perhaps one of the longest sentences ever handed down in a mine safety case," U.S. Attorney Booth Goodwin said after the verdict was handed down, The Associated Press reports. He added that "we wanted to send a clear message and will continue to send that anyone who obstructs our investigation, they're going to be met with the harshest prosecution."

Our Original Post Continues:

Federal prosecutors hope today's sentencing of former Massey Energy security chief Hughie Stover "will send a resounding message" as they pursue charges against higher-ranking executives.

Stover was convicted in October of lying to investigators and attempting to destroy evidence during the federal criminal investigation of the April, 2010, Upper Big Branch coal mine explosion.

Twenty-nine miners died in that massive blast and prosecutors blame Stover, among others, for thwarting federal mine safety regulators as they tried to conduct surprise inspections at the mine before the tragedy.

U.S. Attorney Booth Goodwin argued in a sentencing memorandum that "twenty-nine coal miners thus died in part because of a system of inspection warnings that depended heavily on defendant's leadership."

Goodwin wants U.S. District Court Judge Irene Berger to send Stover to prison for 25 years during a sentencing hearing that begins at 11 a.m. ET in Beckley, W. Va.

Berger rejected Stover's plea for a new trial and a directed acquittal on Monday.

A 25-year sentence would be more than seven times the jail term recommended in federal sentencing guidelines for Stover's crimes, which max out at 41 months. Defense attorney William Wilmoth says prosecutors want what amounts to "a de facto life sentence" for the 60-year-old Stover.

Wilmoth argues that Stover had no direct involvement in the events that caused the nation's worst mine disaster in 40 years. "To suggest otherwise," Wilmoth wrote in his response to Goodwin, "is offensive, it is scandalous, it is libelous, but most importantly, it is false."

Prosecutors are playing tough with Stover because he's the first Massey official to be convicted and sentenced in their Upper Big Branch investigation. The second, mine superintendant Gary May, was charged last week with conspiracy and is scheduled to testify against Stover at today's sentencing hearing.

May's appearance suggests he's cooperating with prosecutors, perhaps as part of a plea agreement. The conspiracy charge against May is based in part on the same system of inspection warnings that resulted in Stover's conviction.

Witnesses appearing for Stover are expected to praise his service in the military and as a police officer. But, prosecutors have witnesses ready to describe alleged acts of sexual harassment and racially-motivated misconduct involving Stover, and "sexually explicit images" apparently found on his computer at work.

The government's witness list also includes Gina Jones, widow of miner Dean Jones, who died in the blast. Jones says she'll "speak on behalf of Dean because he's not here to speak for himself."

Federal mine safety chief Kevin Stricklin is also scheduled to testify about his agency's investigation of the disaster.

A long prison sentence could help prosecutors pursue plea agreements and cooperation as they work up the management ladder of Massey Energy.

Documents released in earlier investigative reports about the tragedy show that the mine was micro-managed by senior Massey officials, including former CEO Don Blankenship. The internal company records and Blankenship's own deposition in another case describe the tracking of coal production minute by minute and foot by foot at Massey mines.

Charges against mining company executives after mine disasters are rare. Convictions and jail terms are even rarer. No mining company official above mine superintendent has been charged since 1992.

Massey Energy pleaded guilty to corporate criminal charges in 2009 after a fire at the Aracoma Alma coal mine in W.Va. killed two men. Last month, Ken Ward of the Charleston Gazette recalled the tragedy on its sixth anniversary. As Ward reported, the company paid more than $3 million in criminal penalties and civil fines and four foremen were charged with misdemeanors but no higher-level officials or executives were charged.

Congressional and mine safety investigators recommended criminal charges after nine miners and rescuers were killed at Utah's Crandall Canyon coal mine in 2007. Five years later, there's no sign of any action or any explanation from the U.S. Attorney's office in Utah.

Alpha Natural Resources absorbed Massey Energy in a merger last year, but escaped corporate criminal charges in the Upper Big Branch explosion by agreeing to a settlement of more than $209 million, which includes payment of outstanding Massey fines, compensation for families of the victims and programs aimed at improving mine safety in the company and industry.

Massey managers and executives "need to be accountable," says Gary Quarles, whose son Gary Wayne died in the tragedy. "It's past time that they got evidence to put people like this in jail."

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