Christ, I'd have to break it down by crime committed.
Serial killers Henry Lee Lucas, Kenneth McDuff. Regular murderer, Jaimie Lewis.(I think, the name escapes me, this was in 91.)
During the McDuff hearings we all waited in the hallways hoping to shoot his ass in case there was an escape attempt.
Lewis was 17 when he executed two little kids in their own home just to see what it was like to shoot someone. (he actually said this in testimony) He picked the house at random, killed the little boy when he answered the door, shot the little girl in the bedroom. Weapon was a Ruger Single-six.
Sexual assault.
Lewis Freeman, hands down. A construction worker who moved constantly, Lewis married a mother with 4 daughters in order to gain access to the girls. The alcoholic mom never said one word as he repeatedly molested each little girl as she grew into his preferred age range. (11-13 yoa) Often, she would be in bed while he was doing it. Anal was his favorite pastime.
No one said a word until the oldest daughter turned 18 and went straight to the police. He got away with it for almost 8 years. He committed so many offenses in different jurisdictions that at one time 11 counties were arguing who would prosecute him first.
A few more stand out for mention,
Louis Sanchez, raped and beat to death a 20 year old jogger with a discarded shock absorber. Her entire head was jelly. There was blood on the bottom of tree branches 15 feet above the crime scene.
The "Groper". A name given a serial rapist by the news media. We never caught him. His method was to run full tilt at a small petite woman in secluded areas and body slam her into a concrete wall or pavement, rape her, then beat her. An incredibly vicious attacker, it was only by purest luck none of the women died. Most of his victims never saw him or even heard him attack. The few eyewitness descriptions we had were so general and fragmentary that they could have fit almost anyone. Large white male in his middle 20's, brown short hair. (The news media put out a composite, which resulted in lots of off duty police officers and military personnel being turned in by their neighbor) Incredibly prolific, he was doing three a WEEK. Then he just stopped.
My theory is he was a UT student who went home. His attacks stopped almost to the day of college graduation. There was also some correlation around class times/campuses. He could easily make an attack between classes then dissappear back into the crowd of students. We'll catch him thru the DNA database someday.