James Nord, Associated Press
In this Aug. 5, 2015 file photo, motorcycles stretch down Main Street in Sturgis, S.D., for the landmark 75th Sturgis Motorcycle Rally. Arrests for DUI are the only category of crimes recorded by the South Dakota Highway Patrol that has not increased this year at the Sturgis Motorcycle Rally, a fact that officials say is due to increased resources being dedicated to a spike in crashes in the region.

SIOUX FALLS, S.D. — This year's Sturgis Motorcycle Rally is estimated to have been one of the busiest on record, but officials with the state Highway Patrol say they've actually seen a decrease in drunken driving arrests, in part because of a spike in traffic accidents in the area.

With only Sunday officially left, the rally and its surrounding towns have already seen 140 traffic accidents that caused injuries and 12 fatal accidents in 11 days, statistics that have dwarfed the counts from 2014. With the jump in crashes, Highway Patrol Capt. Kevin Karley said troopers are left with less time to patrol.

"That's what we anticipated. We knew going into this we were going to have higher attendance and higher traffic numbers," he said. "We knew that it was going to be more difficult to work traffic."

As of Saturday, there were 200 DUI arrests tied to Sturgis; that's almost 30 fewer than the same time last year. And officials estimate the rally is one of the busiest they've seen.

On Monday, the Department of Transportation counted more than 96,000 vehicles entering Sturgis, the highest so far this year but still shy of the one-day record of 110,000 in 2000.

Karley said people driving under the influence is always a concern for law enforcement, but also said that less time being dedicated to traffic patrols likely isn't the only reason for fewer drinking and driving violations.

The increased presence of law enforcement this year and the availability of shuttles mean fewer people are likely driving under the influence, he said, adding that attendees knew well in advance of this year's event that there would be a strong law enforcement presence.

"I think it could very well be that people are making more responsible decisions about drinking and driving this year," he said.

In general, the Highway Patrol has made fewer arrests in most of the categories of crimes that are made available to the public.

Arrests for misdemeanor and felony drug offenses are both down this year, as are warnings. And troopers have issued only 30 more citations. There's even been slightly less cash seized.

Karley said it's likely too early to tell for sure why other categories have spiked.

"We go out and do the work and the numbers just bear out," he said.

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