(CNN) Edward Nero, the second Baltimore police officer to stand trial in the Freddie Gray case, was found not guilty of all charges in connection with Gray's death in 2015.
Nero, 30, was charged with second-degree intentional assault, reckless endangerment and two counts of misconduct in office for his actions the day Gray, 25, suffered a fatal spinal injury in police custody.
After a five-day bench trial, Baltimore Circuit Judge Barry Williams said the state failed to meet its burden of proof. What, exactly, was Nero accused of, and why did Williams clear him of wrongdoing? Here's a breakdown:
Nero was one of three bike officers involved in the initial police encounter with Gray on April 12, 2015. He and Officer Garrett Miller were called to assist another officer, Lt. Brian Rice, who had initially begun chasing Gray.
Prosecutors claimed that Nero assaulted Gray by detaining him without justification. But Miller testified under limited immunity that he alone detained and handcuffed Gray, that he was the one who walked Gray to the wall while Nero retrieved officer Miller's bike. The only time Nero touched Gray at the arrest site was when Gray asked for his inhaler, Miller testified.
Williams gave considerable weight to Miller's testimony, noting it was corroborated by Gray's friend, Brandon Ross.
"Mr. Brandon Ross clearly stated that it was not the defendant who was with Mr. Gray initially but another bike officer. Mr. Ross saw the defendant with two bikes walking towards Mr. Gray and the other officer, and this was after the bike officer cuffed Mr. Gray," Williams said in his ruling (PDF).
"There is no value for Brandon Ross to say this because he is not a friend of the defendant. He saw what he saw, and it corroborates the testimony of Miller stating that he and he alone was involved in detaining, cuffing, and taking Mr. Gray to the wall to await transport."
Williams dismissed prosecutors' arguments that Miller's previous use of them term "we" -- as in "We grabbed him and put him on the ground" -- implicated Nero in Gray's detention or arrest.
Testimony from Miller and statements from Nero suggested the use of "we" is a common practice among police officers, who tend to speak in terms of the collective, he said.
Furthermore, evidence showed that Nero was not present when the detention turned into an arrest, and Nero did not have a duty to question Miller's decision, Williams said.
"Since the defendant's contact with Mr. Gray came after Mr. Gray was detained by Miller, this Court finds that the contact by the defendant was legally justified and not reckless. Therefore, as alleged by the State, there is no assault by the defendant," Williams said.
Prosecutors alleged Nero arrested Gray without probable cause, forming the basis for misconduct in office charge, defined as corrupt behavior by a public official in the exercise of his duties or while acting under color of law.
But because Miller acted alone, Nero did not detain or arrest Gray without probable cause.
The state argued that Nero was criminally liable for Miller's actions as an accomplice. Williams said the state failed to prove that Nero "knowingly aided, counseled or encouraged the commission of the crime" with the intent to make it happen.
"The state's theory from the beginning has been one of negligence, recklessness, and disregard for duty and orders by this defendant," Williams said.
No evidence presented at trial indicated that Nero intended for any crime to happen or that he was willing to support a crime, Williams said.
"The Court does not find that the defendant detained Mr. Gray at the ramp, nor does the court find that any actions by the defendant turned the detention into an arrest; the initial contact concerning detention and arrest occurred when Miller, acting alone, interacted with Mr. Gray."
Nero was charged with reckless endangerment and another misconduct charge stemming from what happened next. Prosecutors called it the second stop after Gray was placed in the van and driven a block or so.
Miller and Rice took Gray out of the van, according to court documents. Miller replaced Gray's handcuffs with flex cuffs and put shackles on his legs, according to court documents.
At this point, Gray went limp, according to testimony. Rice got into the van and pulled Gray by the shoulders while Nero held his legs. Video evidence showed Nero kneeling down and placing his hands on Gray's lower body. Seconds later he removed his hands and Rice jumped out of the van.
The state alleged that Nero's failure to to seat belt Gray in the van rose to the level of reckless endangerment and misconduct in office.
Reckless endangerment is defined as conduct that creates a substantial risk of death or serious injury -- if the actions are found to be unreasonable based on the circumstances presented, and not the end result.
As Williams put it, two questions were at issue:
Could an officer under similar circumstances as Nero expect another officer in the van with Gray to seat belt him, especially if that person was in a higher position?
Could an officer under similar circumstances reasonably assume the van driver would check to make sure Gray was secure before driving off?
"The answer to both of those questions, based on the facts presented, is yes," Williams said. Therefore, he said, it was reasonable of Nero to not take it upon himself to secure Gray and to expect other officers to handle it.
As for the misconduct in office charge, the state had to prove that Nero "corruptly" failed to do an act required of his job. The state presented various pieces of evidence related to officer training and policies for arresting and transporting prisoners but no evidence that Nero received specific guidance on how to secure prisoners or detainees, Williams said.
"The Court is not satisfied that the State has shown that the defendant had a duty to seat belt Mr. Gray and, if there was a duty, that the defendant was aware of the duty," Williams wrote.
"This Court finds that the State has failed to meet its burden to show that the defendant corruptly failed to do an act required."
The case against William Porter, the first officer to go on trial, ended in a mistrial in December after jurors couldn't agree on a verdict. Four officers have yet to stand trial -- Miller, Lt. Brian Rice, Sgt. Alicia White and Officer Caesar Goodson Jr.. The trial for Goodson, the van driver, will start June 6.