The killing of a 92-year-old Atlanta woman during a police drug raid has led to new questions about the practice of "no-knock" raids, the Christian Science Monitor reported Nov. 29.

Kathryn Johnston was shot and killed after she opened fire on a group of police officers who forced their way into her home executing a drug-related search warrant. Three police officers were wounded.

Police say the "no-knock" raids -- where police simultaneously announce their presence and break down doors -- are necessary to prevent suspects from destroying evidence. But the tactics have led to a number of innocent homeowners being killed, often after mistaking police for robbers and using a gun to defend themselves.

Johnston was reportedly frightened of intruders, keeping a gun for protection, barring her windows and adding extra locks as drug dealers moved into her neighborhood. The raid was based on a tip from an anonymous informant, who later recanted a statement that he had purchased drugs in Johnston's house.

Her death has led Atlanta officials to weigh the pros and cons of no-knock raids; 50,000 such raids took place last year nationwide, up from 3,000 in 1981. About 40 bystanders have been killed in such raids, the Cato Institute said.

"We are reviewing all of our procedures, how we obtain warrants and how we apply them," said Atlanta Police Chief Richard Pennington. "I promise that the complete truth [about the raid] will eventually be known."

"The question that society has to answer is: How much risk are we willing to take in order to get violent drug dealers, knowing we're going to make mistakes and shoot innocent people?" said David Moran of the Wayne State University Law School in Detroit.

In other communities where similar shootings have occurred, reforms or cutbacks of no-knock raids have followed.

About 80 percent of no-knock raids are conducted in drug cases. "A lot of drug-dealing goes on in the African-American community, and most African-Americans would like to see the drug dealers moved," said David Bayley, a criminologist at the University at Albany in New York. "As anybody would, they're against unjustified shootings, but they're not all that opposed to police working in a hard-edged way against people who are destroying their security."

The U.S. Supreme Court recently ruled that police should wait at least 15 seconds after knocking before entering a residence, but also allowed evidence from raids where police waited a shorter period or not at all. Experts said the ruling could increase the use of no-knock raids.