Bought used vehicle didn't pass emissions who is responsible

We live in Colorado where emissions is required. We purchased a 96' tahoe. After getting the temp tags we went to get eh emissions and it failed HORRIBLY. We ended up having to pay $350 for part and $300 in labor in order for it to pass. Can we hold the seller responsible for paying this ?Obviously if we knew this was wrong we would have thought a little harder about the purchase.