A former Tulsa reserve deputy who fatally shot an unarmed, restrained suspect after mistaking his gun for his Taser was sentenced to 4 years in prison on Tuesday, the Associated Press reports.

On Wednesday, a former Tulsa deputy who fatally shot an unarmed, restrained suspect after mistaking his gun for his Taser was convicted of second-degree manslaughter, the Associated Press reports.

On Wednesday, six months after a volunteer reserve deputy, Bob Bates, shot and killed an unarmed man, Eric Harris, a grand jury indicted Tulsa County Sheriff Stanley Glanz on misconduct charges. The New York Times reports that Glanz will step down as sheriff.

The Oklahoma State Bureau of Investigation announced on Monday that it is opening a formal inquiry into the sheriff’s office that oversaw Robert C. Bates, the 73-year-old reserve deputy who shot and killed Eric Harris in April, the Associated Press reports.

According to a new report by CBS News, a 2009 internal investigation by the Tulsa Sheriff’s Office into the training of Robert Bates, the reserve deputy who claims he mistakenly shot and killed Eric Harris earlier this month, deemed his training “questionable” and marked by “preferential treatment,” with Bates apparently warning officers “that he could do what he wanted.”

The 73-year-old volunteer deputy who shot and killed Eric Harris after mistakenly drawing his gun instead of his Taser was charged with second-degree manslaughter on Monday, The New York Times reports.

Here's something that almost all the mass killers of the last fifteen years or so have in common: they've been called "nerds." James Holmes, who allegedly murdered 12 people in a crowded Colorado movie theater on Friday morning, was described as a "nerd" by his uncle within hours of the shooting. Norwegian mass murderer Anders Behring Breivik is, in the Telegraph, a "puffy-faced computer game nerd." Columbine killers Eric Harris and Dylan Klebold were "innocuous nerds," the Los Angeles Times claimed in 1999.

The 1999 edition of Rebelations, the yearbook for Columbine High, is fetching bids right now on an online memorabilia auction site. Yes, you can own the yearbook that features murderers and their victims for $500. [Update: The item has been withdrawn. See below.]