The inquiry followed an HRA security department investigation into 37 races staged between July, 2003 and February, 2004.
Culhane, who rode 88 winners for earnings of £850,000 in 2006 and had 15 successes in the first three months of this year before suffering back and neck injuries in a fall in April, was given a one-year suspension from the sport after admitting aiding and abetting individuals to lay or back horses by providing inside information and misleading investigators.
During the seven-hour hearing at the HRA’s Shaftesbury Avenue headquarters, Culhane, 38, pleaded to being "reckless" whilst denying that he was corrupt.
The number of jockeys banned or warned off in Britain within the past two years rose to 12 as Dean Mernagh, 28, was suspended for nine months after admitting passing on inside information for reward.
Mernagh, who has had four winners this year and was also found to have misled investigators, relayed information on 10 occasions to either Culhane or his brother-in-law Gary Lyons, for which he was given £200 each time if the bet was successful.
Lyons, a former jump jockey who became a Press Association race-reader, was excluded for a minimum of two years, while Culhane’s father-in-law Dave Watkins, who, unlike the others, did not attend the hearing and refused to co-operate with the investigation until admitting his guilt at the last moment, was warned off for a minimum of five years.
Watkins and Lyons were found to have used information received from the two jockeys for financial gain. Watkins’ Betdaq and Betfair accounts, which were operated by Lyons, made a profit of £56,000 from the races under investigation.
From the 37 races monitored, horses were laid to lose or backed and only five of the bets was unsuccessful.
Culhane and Mernagh declined to comment afterwards but their legal representative Phil Williams of Evershed Solicitiors said in a statement: "They are both disappointed with the panel’s decision.
"In particular, Tony Culhane has pleaded to being reckless in conversations with family members for which it was accepted Tony Culhane had no financial, or other, reward.
"Mr Mernagh is also extremely disappointed with the panel’s decision. At the moment, we do not have the panel’s written reasons."
Neither rider was accused of failing to ride the horses concerned on their merits.
Paul Struthers, PR manager for the HRA, commented: "This was the last of the high-profile cases that resulted in the HRA charging 10 licensed individuals with corruption related offences last year. These have conclusively shown our determination and ability to root out wrongdoers."
Inside information rules are being tightened further and will apply to all participants in British racing, including journalists.