The teen driver who caught a break after causing a crash that killed a state trooper in 2007 has been arrested again, this time for driving impaired and while his license was suspended.

Cody Loos, now 19, pleaded guilty to driving under restraint after he was stopped in Lochbuie on Jan. 10, when an officer saw him run a stop sign and smelled marijuana. Charges of driving under the influence and possessing drug paraphernalia were dismissed.

"This case was treated like any other case," said Jennifer Finch, spokeswoman for the Weld County District Attorney's Office. "He didn't get some sweet deal here. We looked at the evidence and said we're not going to get a DUI conviction from a jury on this."

When Loos was stopped at 12:42 a.m. on Jan. 10, he had a glass pipe with burnt residue in it in his pocket, and he told officers he had smoked a bowl of marijuana two hours before, according to a Lochbuie police report.

Loos failed a roadside sobriety test, but a subsequent blood test detected no drugs, according to the police report.

Finch said it's not unusual for prosecutors to dismiss DUI charges when a blood test does not provide the evidence needed for a conviction.

"We didn't just dismiss everything. There was a reason behind it," she said. "We didn't have the evidence that we felt we would need to prove the DUI."

Loos did plead guilty to driving while his license was suspended. He paid a fine and served five days on electronic home monitoring.

Loos declined to comment Thursday.

The police report states he knew his license was suspended.

"I had a hearing, and they told me it was suspended," Loos told officers.

In March 2008, Loos was sentenced to two years' probation and ordered to serve 300 hours of community service after pleading guilty to careless driving resulting in death.

Loos, then 17, was at the wheel on Oct. 11, 2007, when he looked down for some sunflower seeds and hit two Colorado State Patrol troopers. The troopers had stopped to help a driver who had lost a 2,500-gallon plastic water tank he was towing on a trailer.

Trooper Zachariah Templeton was killed. Trooper Scott Hinshaw suffered broken bones in his legs but survived.

Loos never spent any time in jail for the accident but was placed on probation, with a deferred sentence.

Officials at the Adams County District Attorney's Office, which handled the 2007 case, said Thursday that nothing has been filed to bring Loos back to court.

At Loos' sentencing, Hinshaw said he did not want the accident to ruin the teen's life.

"Do not let it define who you are," Hinshaw said at the sentencing. "You made a mistake."