Jaco was the epitome of the tortured musical genius.
He was the kind of kid who was good at anything he tried. Good in school, an excellent athlete (it was pronounced "Jocko" for a reason) and when he finally decided to take up an instrument (his father was a jazz musician) he decided to play the drums at first. Passionate enough to rent a warehouse and practice there, he eventually switched to the bass, and loved it to the point of mania.
He had an upright bass, but it started to come apart with the heat and humidity of the Florida town he grew up in (Fort Lauderdale) so he switched to the bass guitar. After playing it extensively, he decided in his frustration at not having the same fluidity he had with his upright to remove the frets and fill in the holes with wood filler, inventing the fretless bass guitar.
With it, he turned an instrument that to date had been used to thud out the root of chords in country, jazz and rock and turned it into an instrument that could slur, trill, and sing, gliding in registers the bass was tricky to play fretted. He practiced maniacally, and developed a level of genius with the instrument that rivaled the virtuosity seen in other instruments.
And the importance of this technical and musical genius cannot be overstated. He transformed the instrument and forever changed the way it was regarded and played. He combined it with advances in technology to play it with chorus, or delay - in one famous solo with Joni Mitchell, he "looped" himself playing three notes with a string slap as a rhythm, creating an impromptu chorded backdrop with which to play gorgeous, soaring octave-doubled melodies.
Lauded mightily on the local scene, he eventually wowed Joe Zawinul of Weather Report and when their bassist quit, Jaco was given the job. He completely wowed the fusion jazz scene, and between Weather Report and a solo effort (whose first album netted him two Grammy awards) became a legend.
But his personal life was a mess. His father had been an alcoholic whose turbulent life had been something Jaco had protected his brother from. He married early and had two children, and when that fell apart had two children with another - in two very turbulent and ultimately crashing and burning relationships. He was a teetotaller until Zawinul one fateful night told him to lighten up and offered him a shot of alcohol. Whatever genetic key was in him that took to booze lit up like a pinball machine, and he rapidly descended into multiple drug addiction.
It gets worse.
Between his stormy relationships and the stress of keeping up his status as living legend, the manic depression that fuelled him to become the tortured genius he was really started to take hold. Between addiction and his increasing inability to manage his mental illness, he became homeless.
From teenage wunderkind to 20something legend, he became a 30something homeless addict, goading people to near-violence, and then charming them, pushing people away and then desperately wanting them back.
He was committed a few times - but the medication that helped his symptoms affected his genius, and also affected his hands. One medication caused tremor, another caused him to lose the feeling in his fingers. He was looking at two choices that seemed suboptimal - a composer who could no longer play the melodies in his head, or a crazy man ranting in the forest.
He chose the latter, cadging for liquor or drugs, pawning or losing the bass guitar that was his only link to sanity. His friends tried to hide it from him, but eventually someone lost or sold it, and it has not been seen since his death.
And yes, he died. One night, he went to a jazz club and tried to go on the stage, drunk and near-incoherent. Security, having no idea who he was, bum-rushed him off stage, and it was the last time he was seen alive and conscious. The head of security would later be arrested.
According to the man who was tried for his murder, Luc Havan, he chased Pastorius, who slipped and fell and hit his head. Nobody bought it, as the injuries to Pastorius' head and face indicated that he had been beaten into a coma, with extensive injuries to his face and skull. It was a coma that he'd never wake from, dying nine days later. Luc Havan pled guilty to manslaughter to avoid a murder charge and trial, but to the horror of Jaco's family (who were ambivalent about their feelings about his death, seeing it as a matter of time) the man was released almost as soon as he went in. Between time off for good behavior, credit given in order to reduce prison overcrowding and so forth he only served just under four of the twenty one months' sentence he received for brutally beating the skinny, undernourished and drunken Pastorius to death.
Everyone, from Zawinul (who blames himself for pressuring Pastorius to have that fateful first drink) to his family have asked themselves over and over what they could have done to stop the downward spiral.
But despite the man's turbulent life and violent death, he's remembered as the man who turned an instrument notorious for being something the lazy choose to play because you only ever play three notes a song into something people truly aim to master and play with musicality and virtuosity. Bassists everywhere genuflect and mention his name in hushed tones in the same way classical musicians speak of Mozart, keyboard players speak of Bach, or violinists revere Paganini.