sign off on 復習
2015年の８人が死亡した列車衝突事故を受けて、アムトラックの速度技師が事故の原因であるとして起訴されました。
Speeding Amtrak engineer charged in 2015 crash that killed 8
The state's top prosecutor on Friday charged a speeding Amtrak engineer with causing a catastrophe, involuntary manslaughter and other crimes in a deadly 2015 derailment that came after he accelerated to 106 mph on a 50 mph curve.
Prosecutors said they were in talks with engineer Brandon Bostian's attorney to have him surrender on the charges.
Pennsylvania Attorney General Josh Shapiro expanded on charges a Philadelphia judge approved a day earlier. The unusual judge's order came after the family of a woman killed in the crash sought a private criminal complaint when city prosecutors declined to press charges as Friday's two-year deadline approached.
The judge had signed off on two misdemeanor charges over Rachel Jacobs' death in the May 12, 2015, derailment. Shapiro approved a felony charge of risking or causing a catastrophe and a string of misdemeanors, including eight counts of involuntary manslaughter and reckless endangerment.
http://abcnews.go.com/US/wireStory/scholar-choices-ahead-order-arrest-amtrak-engineer-47379648
取り上げる表現は、"sign off on"です。"sign off"と"sign on"は反意語でそれぞれ「契約などを破棄する」と「署名して雇われる」という意味になりますが、"sign off on"となると、また違う意味になります。
LDOCEで確認してみると、"to show that you approve of a plan or that something is finished by signing an official document"と定義されていました。『ジーニアス英和辞典』第４版（大修館）では、「（計画などを）承認する」と載っています。(Akim)
