A Sussex County judge also said Friday that there was insufficient evidence against Donaldson.
Police in the southern coastal town of Lewes stopped 79-year-old Donaldson last December for a traffic violation. Police say the officer determined Donaldson had been drinking and gave him field sobriety tests. Donaldson, a resident of McLean, Va., subsequently was charged with drunken driving.
Defense attorney Eric Mooney said Donaldson was "extremely satisfied" with the outcome of the case.
Donaldson's career at ABC News included stints as chief White House correspondent and co-host of "PrimeTime Live" and the Sunday morning broadcast "This Week with Sam Donaldson and Cokie Roberts."
Many US police departments increase the number of DUI checkpoints and DUI enforcement during holidays. For example, Colorado state police have what they call "The Heat is On," 12 specific 12 specific DUI enforcement periods centered on national holidays and large public events.
The Denver Post reports that nearly 400 people in Colorado were arrested on DUI charges during Halloween. The aim is to reduce driving fatalities during heavy drinking periods. In 2012, 24 people were killed in alcohol-related crashes in October, with six occurring over the days surrounding Halloween.
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