A year-long investigation into a gambling ring in Twin Falls consumed "an extraordinary amount" of police manpower but has produced much less than police anticipated - a total of 12 misdemeanor charges against three men, according to Idaho State Police officials.

Authorities say their case was hampered by apparent tip-offs to targets of their investigation, though a subsequent probe of those leaks went nowhere.

The charges stem from a 2007 undercover operation that resulted in seizure of 17 video gaming machines from the Pioneer Club, 1517 Kimberly Road, and from a house at 445 Second Ave. S. Investigators allege the devices were used much like slot machines, with winners paid by attendants.

"Originally, what we were looking at was charging a felony of racketeering and money laundering," said ISP Sgt. Gary Kaufman. "When we completed our investigation ... the (Attorney General) reviewed the case and determined that the only thing that the county could prosecute would be misdemeanor gambling."

Kaufman said he believed the evidence built through surveillance and sting operations carried out by state and local law enforcement last summer showed clear racketeering but that prosecutors didn't agree.

Twin Falls Prosecuting Attorney Grant Loebs was on vacation Monday and could not be reached for comment. Bob Cooper, spokesman for Idaho Attorney General Lawrence Wasden, also declined comment, deferring to Loebs.

State police spearheading the investigation encountered several obstacles, according to Kaufman and court papers.

For example, one of the men charged, Pioneer Club owner Marvin Pierce, told police he knew the raid was coming two weeks before they showed up with a warrant, according to court records. Pierce declined to reveal his source, and an investigation into the alleged leak yielded no results, ISP investigators told the court.

Court records also show that state law enforcement officials received multiple tips about video gaming machines at another, now-defunct Twin Falls bar but took no action. Kaufman said no attempt was made to find machines at the second bar because word of the investigation likely arrived there ahead of police.

In court records, Pierce is quoted as telling investigators "Don't waste your breath...The machines (are) gone."

Pierce, Erik Jonsson, owner of the house at 445 Second Ave. S., and Dale Black, the former owner of the now-shuttered Dale's Dogs restaurant on Blue Lakes Boulevard, each face two misdemeanor gambling charges and two misdemeanor charges of possession of slot machines.

Kaufman said Loebs issued summonses for the men last week, but has not sought arrest warrants.

Jonsson, 35, declined comment Monday. Black, 40, could not be reached through Loren Bingham, an attorney representing him on an unrelated civil matter. Pierce could not be reached Monday evening.

According to court records, undercover detectives carrying hidden video and audio equipment on Aug. 2, 2007, went to the Pioneer Club, bought beer and sat down at a table next to four people playing at six machines. The detectives played and cashed out, court records show.

Law enforcement officers later seized seven video gaming machines and paraphernalia used to record payouts. According to court records, Pierce told them that the machines had been in the bar for eight years and that Black owned all but one, which was owned by Jonsson. Pierce told authorities that Black would clean out the machines every morning and split the money with him.

Pierce also told investigators that several attorneys had advised Black that the machines were legal.

After obtaining a search warrant from 5th District Magistrate Roger Harris on Sept. 10, 2007, Kaufman, an AG's office investigator, a sheriff's investigator, four Twin Falls police detectives and two U.S. Immigration and Customs Enforcement special agents entered the house at 445 Second Ave. S., which is called gambling house "DOA" in court records. They seized 10 gaming machines, controllers wired to the machines, two payout receipts, printer tapes of payouts and hundreds of dollars in cash, according to court records.

They also found a sign reading "Rules of the House," and provided Jonsson's cell phone number for "service, jams and refunds."

Brian Conger, who told investigators he lived in and operated the DOA house in exchange for free rent, identified Jonsson as the owner of the machines, which paid out at five cents per credit, court records said.

Cassidy Friedman can be reached at 208-735-3241 or cfriedman@magicvalley.com.