Paul Hammersley has been suspended for 17 days after stewards concluded an inquiry into a spectacular fall at the Sunshine Coast.
Fellow rider Ryan Wiggins was taken to hospital after his mount Puissance Decheval went through the running rail on November 16.
Wiggins escaped with bruising and was able to ride several days later but Puissance Decheval suffered severe injuries and had to be euthanised.
At an adjourned inquiry, Queensland stewards found Hammersley guilty of careless riding.
They determined Hammersley, who rode Equistar, allowed his mount to shift in when not sufficiently clear of Laudable Lemon which resulted in tightening to several runners.
Chairman of stewards Daniel Aurisch said Hammersley tried to rectify the situation which had to be taken into account when assessing penalty.
Hammersley's ban begins after Saturday's racing and ends on December 20.