The charges drew immediate criticism from demonstrators who wanted more serious charges, as well as the arrests of the three officers involved.
Hankison is not charged with causing the death of Taylor. Rather, the police department said, he "wantonly and blindly" fired into her apartment -- shooting 10 rounds.
According to the Kentucky statute, someone "is guilty of wanton endangerment in the first degree when, under circumstances manifesting extreme indifference to the value of human life, he wantonly engages in conduct which creates a substantial danger of death or serious physical injury to another person."
It is a Class D felony, the lowest of four classes of felonies. The maximum sentence is five years; the minimum is one year.
If convicted, Hankison faces five years imprisonment for each count, Attorney General Daniel Cameron said at a press conference Wednesday. A Class A felony -- for example, a murder charge -- carries a sentence of up to 50 years or life, and a minimum sentence of 20 years.
Hankison's shots came "from outside a sliding glass door and through a bedroom window," according to a statement from the attorney general's office. Some of the bullets went through Taylor's apartment and into one next door, where three people were inside, including a pregnant woman and a child.
The three counts are for each of those people in that apartment, and each charge states that "under circumstances manifesting extreme indifference to human life," Hankison "wantonly shot a gun."
"There is no conclusive evidence that any bullets fired from Detective Hankison's weapon struck Ms. Taylor," the attorney general's statement said.
Taylor was shot multiple times in her home by police carrying out a drug investigation. Her death sparked months of protests and has garnered attention across the country. Cameron told reporters that the officers were "justified in their use of force" because Taylor's boyfriend fired at them first.
Sgt. John Mattingly and Det. Myles Cosgrove were not charged.
Of the 22 shots fired by the two that night, six struck Taylor, according to the attorney general, and "medical evidence shows that Ms. Taylor would have died from the fatal shot within seconds to two minutes after being struck."
Retired Sgt. Betsy Brantner Smith, spokesperson for the National Police Association, said situations such as the officers were in that night are "very dangerous" and "dynamic."
"The officers have no choice. They can't just run away, and they can't just stand there and get killed," Smith said.
"It was a very good decision on the part of the state to put this before a grand jury," Smith said. "It's a convened group of citizens. So, the citizens of the state, or some citizens of the state of Kentucky, made this decision based on the facts presented."
Professor Philip Stinson with the Criminal Justice Program at Bowling Green State University in Ohio said he wasn't surprised by the lesser charges.
Stinson keeps a tally of on-duty police shootings and the consequences, and of the some 1,000 of these each year, "and only a handful of times each year . . . is an officer charged with murder or manslaughter resulting from these shootings."
While officers can legally use deadly force if they feel they are imminent danger, that's a hard sell for prosecutors who have to explain that to victims' families, Stinson said.
Ben Crump, an attorney for Taylor's family, railed against the charges, saying they should have been "wanton murder."
"How ironic and typical that the only charges brought in this case were for shots fired into the apartment of a white neighbor, while no charges were brought for the shots fired into the Black neighbor's apartment or into Breonna's residence," Crump said in a statement.
"This amounts to the most egregious disrespect of Black people, especially Black women, killed by police in America, and it's indefensible, regardless of how Attorney General Daniel Cameron seeks to justify it."