Prosecutors determined that ambiguities in Florida's campaign finance laws and the statute of limitations preventing prosecution over campaign expenses more than two years old meant they could not charge Rivera, sources close to the case told The Miami Herald.
"Prosecutors also concluded that Rivera did not break any laws by raising hundreds of thousands of dollars in secret donations to a campaign for an obscure post within the state Republican Party," the Herald reports.
The Miami-Dade State Attorney's Office told TPM that it would not comment before the release of a "close-out" memo, which is expected this week.
The decision to end the probe comes even though a report made public this week shows that a Florida Department of Law Enforcement (FDLE) investigation into Rivera's activities last year identified "possible criminal and ethical violations."
Among other things, the report states that, "From 2006 through 2010, FDLE identified approximately $65,000 in what are believed to be non-campaign related credit card charges that were paid for with campaign funds. These expenses included but were not limited to; pet services, dry cleaning, dental care, medical services, entertainment and travel expenses for his girlfriend." The report was turned over to Assistant State Attorney Joe Centorino on July 29, 2011.
In a statement to the Herald, Rivera's campaign said the congressman had "at all times acted in compliance with both the letter and spirit of Florida and federal campaign finance laws and has timely and properly reported all personal income."
"In essence, FDLE launched a fishing expedition that became a wild goose chase and which has now proven to be a discredited, unwarranted and politically-motivated witch-hunt resulting in Congressman Rivera's exoneration," the statement said. "FDLE's unprofessional waste of taxpayer dollars in this matter is shameful."
Though the state investigation is over, Rivera is not out of the legal woods yet. He's still facing an investigation by the FBI and the IRS over a half-million dollar payment made by a Florida dog racing track to a company connected to his mother and godmother. As reported back in 2010, the money was sent in 2008 by the dog track to the company tied to Rivera's mother after Rivera, then a state lawmaker, helped out on a campaign to approve slot machines.
Messages left with Rivera and his office were not immediately returned.
Read the full Florida Department of Law Enforcement report from July 2011: