A sibling pair of veteran Acadiana horse jockeys with successful but controversial histories in winning races are implicated in an alleged race-fixing scheme at the Evangeline Downs racetrack in Opelousas.

Louisiana State Police on Thursday announced the arrests of brothers Joe Patin Jr., 46, and Billy Patin, 51, who are accused — along with 24-year-old newcomer LeSean Conyers — of manipulating the outcome of a June 19 race at the racetrack.

The Patin brothers also are accused of using hand-held shocking devices — often called names like “buzzer,” “battery” or “machine” — while competing in two July 4 races at Evangeline Downs.

The investigation stems from a complaint received from the Louisiana Racing Commission accusing the three jockeys of “questionable riding tactics that affected the outcome of the race,” State Police spokesman Brooks David said in a news release.

Investigators determined the jockeys “willfully schemed to hold back a horse picked as a favorite to win,” also using a third party to place “unusual bets in an attempt to maximize winnings,” David said.

Police on Wednesday evening arrested Conyers and the Patin brothers on counts of “willful pulling of the reins” and “cheating and swindling.” The Patin brothers also were booked on a count of unnatural stimulation of horses — an illegal tactic used to spook horses into running faster.

Joe Patin had bonded out of the St. Landry Parish jail by Thursday evening on a $20,000 bond, Billy Patin on a $15,000 bond and Conyers on a $10,000 bond.

It’s unclear which races are in question and what kind of penalties, if any, have been lodged against the three jockeys following their arrests.

Louisiana Racing Commission officials on Thursday had not returned phone calls from The Acadiana Advocate. A spokesperson for the Nevada-based Boyd Gaming Corporation, which owns Evangeline Downs Racetrack and Casino, also had not returned a request for comment.

Since April 8, Evangeline Downs has been hosting its annual thoroughbred racing meet. A total of 84 racing days have been scheduled from Wednesday through Saturday until Aug. 29.

The jockeys rode in multiple races without a first-place win on June 19, the first raceday under investigation, but the Patin brothers each placed first in races on July 4 — the raceday they’re both accused of using electronic shocking devices.

Billy Patin claimed victory aboard Heatseeker Sharon in the eighth race that night, with Joe Patin winning on Nadia Anne in the 12th race.

Whether or not they’re occurring without formal complaint, reported instances of race-fixing are rare in Louisiana, said Ed Fenasci, executive director of the Louisiana Horsemen’s Benevolent and Protective Association, of which trainers and horse owners are a part.

“We’re obviously against anyone cheating. We don’t condone it, and we support the Racing Commission in its efforts,” Fenasci said Thursday.

At least for one of the brothers, it’s not the first time he’s been accused of cheating.

Arkansas regulators suspended Billy Patin for five years in 1999 and recalled his $300,000 purse for using a buzzer to win the Arkansas Derby on the colt Valhol, costing him a $2,500 fine and a trip to the Kentucky Derby.

Recorded footage from that race shows a black object falling from Patin’s left hand after the horse crossed the finish line, according to media reports from that time. A tractor driver for the racetrack later found a shocking device on the ground in that area.

The younger Patin — known around the racetrack as “T-Joe” — has a career checkered with arrests and suspensions involving substance abuse.

In 1999, a few months after Billy Patin’s high-profile suspension for cheating in the Arkansas Derby, the Louisiana Racing Commission revoked Joe Patin’s license when he refused to submit to hair analysis. It marked his sixth violation at the time of the racing commission’s substance-abuse rules, according to media reports.

Police arrested him the same month in the burglary of an uninhabited dwelling in Shreveport, a charge for which he later received a first-offender pardon. Nine years later, in 2008, authorities booked him on counts of crack-cocaine possession and reckless driving after his involvement in two traffic accidents in one night, one of them a hit-and-run.

More recently, in 2013, police escorted Joe Patin off the Evangeline Downs racetrack in handcuffs when he confronted and became aggressive with fellow jockey Diego Saenz after a race.

The brothers have been suspended since July 8, when State Police and the Racing Commission commenced their investigations into the allegations, according to an article from trade publication the Paulick Report.

Even after two weeks without mounting a horse, the brothers on Thursday afternoon were still listed among the top 10 jockeys at the Evangeline Downs meet. In sixth place, Billy Patin’s purse totaled about $480,000. In fourth place, Joe Patin’s had about $650,000.

Follow Lanie Lee Cook on Twitter, @lanieleecook, or contact her by phone at (337) 534-0825