BOISE - A Boise man accused of killing a 25-year-old in a drunken-driving crash during the early hours of St. Patrick's Day pleaded guilty Monday to one count of of vehicular manslaughter and one count of driving while under the influence, the Ada County Prosecutor's Office said Monday.

Austin Eugene Campbell was spotted by another motorist swerving "like a NASCAR driver" moments before the rollover, prosecutors say.

According to Prosecutor Katelyn Farley, a man driving to work on the Connector told police he saw a 2003 Toyota Rav4 coming up very fast behind him in the left lane. When the vehicle was about two car-lengths away, the witness said, the other driver jerked the wheel, "darting like a NASCAR driver attempting to pass," Farley said.

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According to police, the Rav4 went off the Connector and across the ramp to Fairview Avenue, rolling an unknown number of times.

Jacob Cecil, 25, of Boise was killed.

Prosecutors said Campbell was driving friends home from a bar and lost control of his vehicle while trying to exit the Connector.

Two other passengers suffered major injuries and a fourth passenger also was injured.

Farley has told KTVB that Campbell admitted drinking $1 beers at Suds Tavern, but would not tell investigators how much he had consumed. He also refused to consent to a blood draw to test his blood alcohol content, but police got a warrant and took the blood sample anyway, according to the prosecutor.

Prosecutors said Campbell's blood alcohol level was determined to be .211.

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The felony manslaughter charge carries a potential penalty of up to 15 years in prison and/or a $15,000 fine. The other charge carries a potential penalty of up to 15 years in prison and/or a $5,000 fine.

Prosecutors said Campbell accepted a plea agreement in which the state will recommend a prison sentence of six years fixed, and nine years indeterminate, for a total sentence of fifteen years, on each count. It will be recommended that the sentences run concurrent.

A second count of aggravated driving while under the influence will be dismissed as part of the agreement, and he defendant can argue for a lesser penalty.

Sentencing is scheduled at 9:30 a.m. August 25.