MARTIN COUNTY — Nine people were released from the county jail over the weekend after Sheriff William Snyder fired a road patrol deputy when tests revealed substances that were the basis of some of his narcotics arrests were not drugs.

Deputy Steven O'Leary arrested the nine people on narcotics charges, in three separate cases, after he reported positive field tests for drugs. But those substances came back from laboratory testing lacking any narcotics, the sheriff said.

The Sheriff's Office did not release any information on the nine people released from jail.

"In all three cases, the evidence, according to O'Leary's reports, field tested positive for illegal narcotics and he made an arrest," Snyder said at a Tuesday afternoon news conference at the Sheriff's Office.

In one case, the substance was a powder commonly used to treat headaches; in another case, the substance was revealed to be a sand-based material having no positive presence of any illegal narcotics, he said.

The State Attorney's Office notified the Sheriff's Office on Jan. 9 about discrepancies with the nine arrests.

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O'Leary's motive is unclear, Snyder said.

"There is absolutely no ethnic, racial or gender issue that sticks out (about the arrests)," Snyder said. "This was across the board, all races and all genders."

He said O'Leary was hired Feb. 1 and came to the Martin County Sheriff's Office with a "clean prior work history" from two law enforcement agencies.

O'Leary worked for the Town of Palm Beach Police Department from May to October 2017 and was employed with the Marion County Sheriff's Office the prior year, according to his personnel file.

O'Leary made 80 drug-related arrests during his probationary period in Martin County, which was about 11 months, Snyder said. He worked mostly nights, covering areas throughout the county.

Snyder said seven or eight detectives are in the process of combing through all of O'Leary's reports from the past 11 months to make sure there aren't any other discrepancies.

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Snyder noted the nine jail releases were somewhat complicated.

"Some of these people had (U.S. Immigration and Customs Enforcement) detainers; some of them had warrants from other places. We had to work through legitimately getting them out of jail," Snyder said.

There are no charges against O'Leary, Snyder said, although he said a charge of official misconduct is possible.

Snyder said the agency's focus now is to "do everything we can to make this as right as possible."

"The culture here is one of honesty and integrity. I know that and I feel that every day," Snyder said. "This was a complete outlier activity; this is not an indication of systemic issues with the Martin County Sheriff's Office."