Rịba ama amaokwu a dị n'okpuru ma zaa ajụjụ ahụ mgbe e mesịrị n'otu asụsụ ahụ dị ka amaokwu ahụ:  Mgbe ọ nwetasịrị Juris Doctor na 1973 site na Mahadum Virginia School of Law, Mueller rụrụ ọrụ dị ka onye na-ekpe ikpe na ụlọ ọrụ Pillsbury, Madison na Sutro na San Francisco ruo 1976. O mechara jee ozi afọ iri na abụọ n'ụlọ ọrụ ndị ọka iwu United States. Ọ buru ụzọ rụọ ọrụ n'ọfịs onye ọka iwu US maka Northern District nke California na San Francisco, ebe ọ ghọrọ onye isi nke ngalaba mpụ, na 1982, ọ kwagara Boston ka ọ rụọ ọrụ n'ọfịs onye ọka iwu US maka Massachusetts dị ka onye enyemaka United States Attorney, ebe ọ nyochara ma gbaa ikpe gbasara aghụghọ ego, iyi ọha egwu na nrụrụ aka ọha, yana izu ọjọọ na ịkwa ego mba ụwa.Mgbe ọ rụsịrị ọrụ dị ka onye mmekọ na ụlọ ọrụ iwu Boston nke Hill na Barlow, Mueller laghachiri na ọrụ gọọmentị. N'afọ 1989, o jere ozi na Ngalaba Ikpe Ziri Ezi nke United States dịka onye enyemaka nke Attorney General Dick Thornburgh na dịka onye na-arụ ọrụ dịka osote Attorney General. James Baker, onye ya na ya rụkọrọ ọrụ n'ihe gbasara nchekwa mba, kwuru na ya nwere "ekele maka Iwu na iwu iwu".N'afọ 1990, ọ ghọrọ onye enyemaka nke United States Attorney General na-elekọta United States Department of Justice Criminal Division. N'oge ọ nọ n'ọchịchị, o lekọtara ikpe ndị gụnyere nke onye ndu Panama bụ Manuel Noriega, Pan Am Flight 103 (Lockerbie bombing) ikpe, na onye isi ezinụlọ Gambino John Gotti. N'afọ 1991, o kwupụtara na gọọmentị na-enyocha Bank of Credit and Commerce International (BCCI) kemgbe 1986 na mgbasa ozi mgbasa ozi. N'afọ 1991, a họpụtara ya ka ọ bụrụ onye otu nke American College of Trial Lawyers. N'afọ 1993, Mueller ghọrọ onye mmekọ na Boston's Hale and Dorr, ọkachamara na ịgba akwụkwọ mpụ ọcha. Ọ laghachiri n'ọrụ ọha na eze na 1995 dị ka onye ọka iwu kachasị elu na ngalaba igbu ọchụ nke District nke Columbia United States Attorney's Office. N'afọ 1998, a họpụtara Mueller ka ọ bụrụ onye ọka iwu US maka Northern District nke California ma nọrọ n'ọkwa ahụ ruo n'afọ 2001.  Ajụjụ: Ebee ka Mueller si nweta nzere Juris Doctor ya?
Mahadum Virginia School of Law