get 是動詞, 帶有 "變成某個狀態" 的意味, 常用 get + adj , 像是 get angry, get excited ... 等. deranged 這個字本身就是個形容詞, 是紊亂的意思. 所以regulation get completely deranged 就是規則或規律整個亂掉了.
go postal / to go postal 1. Slang. To become extremely angry or deranged, especially in an outburst of violence. 變的非常生氣或失去理智，尤其是在有暴力的暴發時
...rise in Star ferry fare became focused on hunger strike of a deranged youngman and led to Riots in Kowloon. Many demonstrations...