surrender, not confiscate
You can't take a seat without the owners permission. That's called stealing. Getting certified gives you an education, but it doesn't give you rights and privelages beyond the average citizen. We can explain why the seat is not safe to use and ask that they turn it over to us, but we have no authority to seize it forcibly. Some techs might get a little creative in their wording to make it appear that they have that authority but I have never felt comfortable doing so. Personally, I prefer to say that someone surrendered a seat rather than that I confiscated it. That more accurately reflects the situation.