This much is known: On the evening of March 14, the 70-year-old Banjo was surrounded by armed officers outside the Eastmont Mall police precinct commanding him to relinquish the cast-iron 9-mm Berretta replica pistol he was holding. He did not.
Police said they demanded he drop the pistol for several minutes. Instead, Banjo raised his head and the pistol toward police. An officer shot and killed him with a bullet to his chest. It was shortly before 7 p.m.
The question burdening those who knew him is how Banjo by all accounts a talented printmaker and peaceful person came to be standing in front of police with a fake firearm at sunset on 73rd Avenue.
And why a 160-pound elderly man was shot by an assault rifle instead of a non-lethal weapon.
"We want to get to the facts. How did we get to here?" said Banjo's niece, Akili Banjo. "We can't get the closure because questions about what happened are not being answered."
The bottom line, police said, is that only Officer Tim Martin can fully answer why he felt Banjo was enough of a threat to police to shoot him.
Police who had surrounded Banjo called for an officer trained to use a non-lethal bean bag round, which can still be dangerous if used incorrectly.
That leaves the basic command "put down your gun," Assistant Chief Howard Jordan said.
"If you fear for your life, there is not much room for negotiation," he said. "It is a split-second decision."
Meanwhile, mourners are left with heavy hearts and minds.
Banjo was "just the most beautiful, gentle spirit you'd ever want to meet," said Duane Deterville, co-author of "Black Artists in Oakland," in which Banjo was included. "That's why it's so upsetting to me. ... I'm really very outraged, to be honest with you."
Legend has it bricks surrounded Banjo as a boy in St. Louis everywhere he looked.
The bricks were to become a motif in his work, including a trademark brick-patterned suit that he spray painted with the words "express yourself."
That's what he did, said his niece. He was irreverent and political. When Nike tennis shoes were the rage, he spray-painted a cheap pair of sneakers and wore them proudly as a statement.
He belonged to the Bay Area Black Artists collective, which helped to define the black aesthetic in visual arts.
He taught art to children and the disabled and in the early years to women who were shunned as unwed mothers.
For decades, Banjo was a member of the Black Filmmakers Hall of Fame, which began in Oakland in 1973, creating a parallel Hollywood Walk of Fame by making prints from the hands of such stars as Harry Belafonte, Eartha Kitt, Sammy Davis Jr., and Sidney Poitier.
The works he exhibited at a 1993 Oakland show depicted some of the subtle scars people suffer from painful experiences in their lives.
He had his own.
Darkness followed his family from Memphis, Tenn., where Banjo was born, to St. Louis, then to Oakland.
Banjo's father, Tommy White, murdered Banjo's brother and mother, who was pregnant.
White then attacked his four other children with the axe. A neighbor shot White to death when he tried to attack him.
That was 1944.
Their aunt Lucille Banjo adopted the four orphans and raised them in Oakland.
One of the brothers, Septha Banjo, an aspiring artist, was convicted in 1960 of murdering two elderly men after robbing them. The reason, the 18-year-old told investigators, was thundering pain in his head and that he needed money to pay for his studies at Oakland City College.
Aside from the early family trauma that left Casper Banjo with a metal plate in his skull, he had to deal with learning disabilities, epilepsy, racism and poverty.
He had few resources as a young artist so learned to be inventive, his niece said.
He served in the Marines as a cook in the 1950s and later traveled widely in Africa and Asia.
"He was an overcomer and he stayed happy," Akili Banjo said.
He came from an artistic family but his talent blossomed as a student at Laney College, where he studied art and later worked as an assistant instructor.
He earned bachelor's and master's degrees in art from the San Francisco Art Institute, where he later taught.
He exhibited his art nationally and internationally from New York to Nigeria.
He also was a member of the prestigious California Society of Printmakers.
His master's level of beauty and clarity is evident in an intricate, haunting 2004 print titled "Life and Death."
The Monday after his death, the curator of prints for the Library of Congress was looking at his work.
He was very close to becoming worthy of the level of the Smithsonian, said fellow artist TheArthur Wright.
All the while, he was working from his small Section-8 subsidized apartment on 69th Avenue and MacArthur Boulevard, near where he was killed.
He walked past the Eastmont Mall in the mornings to exercise after quadruple bypass heart surgery last year.
Banjo disliked living in East Oakland and Deterville and said he feared nearby drug dealers and was cautious not to linger on the street for too long for fear of becoming a target.
A worker at the Center for Elders Independence called the family Thursday as they were preparing for Banjo's funeral to say he could move next week to a board and care facility. He wanted to live in a place where people eat breakfast and dinner in the kitchen, his family said.
Akili Banjo said she could not fathom why he was out during the evening because he usually called her when he left his home.
She said Banjo had complained to her and his doctor at the Center for Elders Independence, which supervised his medical care, that the medication he had recently been prescribed was making him feel anxious (he took four medications and the latest one was changed a month ago).
I just didn't realize it could be worse than he thought it was," she said.
She said she worried about his health but emphasized that he wasn't mentally unstable.
He could have been confused, however, during the confrontation with police, and she wondered if he had suffered a seizure while officers were commanding him to drop the replica gun. She said Banjo would "black out" during a seizure and remember nothing, as is common among some forms of epileptic seizures.
Wright said Banjo did not sound depressed or mentally out of sorts when the two talked by phone the day before the shooting.
The idea of Banjo threatening anyone with a gun was "bizarre," Wright added, echoing the reaction of a dozen colleagues and family members.
Deterville said it boiled down to black men young, old and in between being profiled as dangerous. Racism is the "elephant in the room," he said.
Police, he said, should be able to discern whether someone is a real threat.
It is extremely hard to tell if a gun is fake and police don't have enough time to say "Hey, is that a real gun?" if they feel their life is in danger, said Officer Roland Holmgren, as he displayed a picture of the replica 9-mm Beretta pistol Banjo was holding.
The replica model is so common it can be bought from online vendors and closely resembles a real one.
But that is little comfort to his family.
"It hurts that he's gone. He was really loved," Akili Banjo said.
A funeral will be held 11 a.m. Wednesday at the Baker-Williams Funeral Home, 980 8th St. Anyone wishing to express condolence can also e-mail CasperBanjo@hotmail.com.
Staff writer Angela Woodall can be reached at firstname.lastname@example.org or at 510-208-6413.