Aaron Francis Engler was arrested for disorderly intoxication and resisting arrest without violence in October after a police officer found him lying on a street corner. Initially unresponsive, Engler "started arguing with me and throwing his arms around while I was conducting a pat down," the officer wrote in his report, which also noted Engler's bloodshot eyes and the strong smell of alcohol.

Prosecutors, however, now say that "Engler’s conduct does not constitute disorderly intoxication," CBS News reported Friday.

"Mr. Engler did not endanger the safety of another person, nor was there a public disturbance,” prosecutors said, according to CBS.

Prosecutors also say the pat-down was "likely improper," strengthening Engler's defense and making a conviction "highly unlikely."

"A legal argument could be made that Mr. Engler’s actions, considered to be resisting, were a reaction to an unlawful search," prosecutors said, according to CBS. "This makes proving the State’s case beyond a reasonable doubt highly unlikely.”

The Engler episode was just one in a string of embarrassments for the Secret Service last year. In April, a number of agents were implicated in a drinking and prostitution scandal in Colombia as they prepared security for a visit by Obama. The incident caused an uproar on Capitol Hill, where Republicans launched an investigation into whether Obama's security was ever breached. A number of agents resigned in the wake of the scandal.