The gist of the defense argument was that no one had actually been endangered by Dennis because, it turned out, the firing pin of his gun had been removed and the weapon couldn't be fired.

辩护的中心是实际上丹尼斯并没威胁到任何人，因为，原来那支枪上的撞针事先被卸掉了，所以那支枪根本不能用。

youdao

Just days after the Newtown shooting, Michigan Gov. Rick Snyder vetoed legislation letting concealed weapon permit holders including teachers carry guns in schools, because there was no provision for local school districts to opt out.

WSJ: Even in pro-gun states, bid to arm teachers stalls