GPs in Jersey have made nearly 2,500 disallowed referral claims to the Social Department over the past year.
The rebates - money which is given to doctors when they treat patients - is claimed from the Social Security Department.
Senator Sarah Ferguson has questioned them over how many false claims there have been, what action is taken when that happens and what checks and balances are in place.
Social Security Minister, Deputy Francis Le Gresley says claims are checked automatically and invalid claims are rejected.
They are checked by an IT system which automatically rejects multiple claims for the same consultation.
It also alerts the department if a patient has more than one visit or claim within 24 hours from the same surgery.
Payment is not made unless the surgery can confirm the two claims are genuine.
If a GP were to falsely claim, this can be classed as fraud and referred to the Police.