A former All Black, now a chiropractor, Dean Kenny has been convicted for fraudulently billing ACC for treatment sessions his clients never received.

Kenny, a halfback for the All Blacks in 1986 and an Otago player between 1981 and 1989, last week pleaded guilty in North Shore District Court to 28 charges under the Crimes Act.

The charges related to fees invoices he sent ACC for chiropractic services at two Auckland clinics in Orewa and Takapuna, where he was a registered ACC provider, ACC said today.

The invoices claimed 28 of his clients had received 16 treatments each, when in some cases they had received as few as two sessions.

ACC launched an investigation last September after a client complained about invoicing irregularities.

The investigation found Kenny he had been invoicing for more sessions than his clients had received.

In an interview with an ACC investigator, Kenny said he would book in a "block of treatments" for his patients so there were sessions "in the bank" if they needed more treatment.

However, he had not refunded ACC for treatments not used by patients.

Kenny was sentenced to 225 hours' community service and ordered to repay $7956 to ACC.

The presiding judge said the offence was an abuse of trust of a scheme funded by New Zealand tax payers.

ACC claims management general manager Denise Cosgrove said she welcomed the conviction.

"ACC funds are meant to help injured New Zealanders, not fraudsters," she said.