Good morning, Robert,
The person who is suing you will be laughed right out of Court. There is no Statute, or case law setting any such precedent for this type of lawsuit, nor is there any Statute or case law proving the negative, i.e., that it is not the instructor's fault. It is so ludicrous, I cannot believe he's suing anyone for this.
If I were in your position, I would argue the clear facts ,i.e.,
1. How did he operate a forklift for a full year without any accidents if you did not instruct him properly;
2. Maybe he was not giving you his full attention when you were instructing him;
3. Maybe, he did not study hard enough;
4. Maybe, he did not do all of his homework assignments.
After he finishes presenting his case and you finish your arguments, you should ask the Judge to award you damages in the amount of $5,000 because of his malicious use of process, bringing a frivolous lawsuit, and wasting the Court's time, the Judge's time, and your time.
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