More than a year after Baltimore State's Attorney Marilyn Mosby stepped in front of the cameras to announce charges against six police officers in connection with the arrest and death of Freddie Gray, the state has yet to secure a conviction against any of the defendants. And, with the start of a second trial, the prospects of Mosby's team delivering guilty verdicts this spring look about 50-50.

One charge against Officer Edward Nero looks really weak, another puts him in some jeopardy. Let's take the easy one first.

On its face, the charge of second-degree assault seems dubious, and it might be a loser out of the gate. The prosecution will attempt to prove that Nero had no business arresting Gray and, therefore, handcuffing him on April 12, 2015, constituted assault.

In other words, instead of having made a mistake, Nero is accused of committing a crime.

It appears that he made a wise choice in opting to be tried by a judge instead of a jury because it's hard to imagine any experienced judge buying that argument — that a bad arrest constitutes a crime.

That doesn't excuse Nero's action, but it makes the common-sense distinction of an alleged error in judgment from a punishable misdemeanor.

I could be wrong about the judge-versus-jury decision because it might be impossible to persuade a Baltimore jury that Gray's arrest constituted a crime. On the other hand, going with a bench trial, with Judge Barry Williams, gives Nero even more of an advantage.

Last year, when Mosby decided to charge just about everyone involved in the events leading to Gray's death, the public got the picture of six officers contributing to some aspect of Gray's fatal injury. The citizen-made videos of Gray being held on the ground, then held and dragged, moaning and wailing, to the police van, contributed to that impression of assault.

But, we've learned new things since then — for one, that the injury that caused Gray's death, according to the medical examiner, occurred during his transport in the police van. (Most of us at first thought the injury occurred on the sidewalk near the Gilmor Homes as Nero and his colleagues arrested Gray.)

And, with all the defendants granted separate trials, it has been possible to see specifically what each officer is charged with.

We got a good look at Officer William Porter's part in all this last year. His jury ended up deadlocked in December, and Judge Williams declared a mistrial.

Now, with Nero's trial upon us, away from the emotions and political grandstanding of last May, we can see what Mosby has for a case. And it's dicey.

Prosecutors are going to try to prove that, in a high crime area of West Baltimore, just three weeks after Mosby's office had asked police to target the neighborhood with “enhanced” drug enforcement efforts, Nero did not have cause to arrest Gray after he made eye contact with officers and took off running. And, because Nero and his colleagues did not have cause to arrest Gray, putting handcuffs on him amounted to misdemeanor assault.

Essentially, the Baltimore state's attorney's office has decided to set a new standard: Cops who make bad arrests will face criminal penalties. Instead of just being chewed out by a District Court prosecutor or by a police commander, instead of being disciplined, or being sued by an offended citizen, we're going to charge cops with assault?

I realize that some people think this might be a long-overdue reform, a remedy to bad arrests, but it's more likely to cause police officers to back off from pursuing suspects in street crimes. If a cop plants evidence on a suspect, if a cop has a history of harassment, that's a different story. But if a cop has a reasonable suspicion of a crime, what do we expect him to do, take a pass?

(I've written plenty about the futility of the war on drugs. When I speak of cops pursuing suspected criminality, please note: I'm referring to property crime, gun crimes and crimes of violence. I am not talking about chasing drug addicts or dealers into alleys, even though the law says they still can. Freddie Gray was as much a victim of the war on drugs as anything else.)

While I have big doubts about Mosby's second-degree assault charge against Nero, the 30-year-old officer also faces a charge of reckless endangerment. That relates to the nightmarish way Gray was placed in the police van.

“This case,” the state said in motions last fall, “involves the risk to a prisoner created by transporting him in a police vehicle resembling a steel cage without a seatbelt — while his hands and legs are physically restrained from movement.”

The state might only have to convince Williams of a grave risk of injury to Gray to get a conviction on the endangerment charge. I don't have a hunch about how that part of the case might go, but it's certainly not as dubious, prima facie, as that assault charge.

drodricks@baltsun.com