The retired "engineer" can talk about engineering, he just can't present expert witness in a trial. Also, he was never licensed as an engineer, it's not as if

The retired "engineer" can talk about engineering, he just can't present expert witness in a trial. Also, he was never licensed as an engineer, it's not as if his engineering license lapsed after testimony. You can throw out all expert testimony in the US if you wish, I guess that would put CSI out of business.