Literally: disorder – violence – wolf – spread
Alternately: To engage in violent and unlawful behavior; to ignore reason and act wildly and destructively. Rioting; committing outrages.
Notes: It is an error to replace 藉 with homophone 籍, “register” (note the 艹 “crown” in one and the ⺮ in the other). So is reading 暴 as baku, although that can be a valid pronunciation in other contexts.
This is a doubled-for-emphasis type of yojijukugo; both 乱暴 and 狼藉 refer to “violence.” Supposedly the latter invokes the image of a patch of disturbed grass where a wolf has lain down to sleep. The compound may be made into a verb phrase by following it with ～を働く (~wo hataraku).