JACKSONVILLE, Fla. -

Sheriff John Rutherford says an internal affairs investigation of a veteran Jacksonville detective accused of threatening the president and members of the Democratic Party last week is not necessary since the officer involved elected to retire.

In response to an open records request from Channel 4, Rutherford said the Jacksonville Sheriff's Office learned last Friday of "threatening statements allegedly made by one of our detectives (Sam Koivisto) earlier in the week."

Rutherford said in a preliminary interview with Koivisto, he acknowledged making the statements, which "we found his comments to be unacceptable workplace conduct, as opposed to legitimate threats."

DOCUMENT:  Sheriff Rutherford's letter on Detective Koivisto

Given the nature of the comments, the JSO notified the United States Secret Service of Koivisto's statements.  The Secret Service told Channel 4's Scott Johnson they will not comment on their investigation, but a decision on any possible charges would be up to the U.S. Attorney's Office.

Rutherford said Koivisto, who has 24 years with the department, elected to retire early.