"He was slammed down to the ground, his face hit the concrete, he was put in a very painful -- what’s called a figure four leg lock twice. They also put their fists in his chest, all before he offered any real resistance," Adachi said, adding that Smith started to resist only after informing officers that his partner, Andrea Appleton, was pregnant.
"This is also a situation where his pregnant girlfriend was thrown to the ground, the officer’s knee was in her back 20 seconds after both she and Michael told the police she was pregnant," Adachi said. "As a result, they lost the baby."
Appleton told the San Francisco Chronicle this week that she suffered a miscarriage about two weeks after the incident. The public defender's office did not respond to inquiries seeking any medical evidence that the miscarriage was related to Smith's arrest or Appleton's handcuffing.
The case comes at a time of scrutiny of police use of force and several shootings of young men of color throughout the Bay Area and the rest of the country.
But the judge presiding over Smith's case disallowed mention of other cases during the trial, including that of the fatal BART police shooting of another young black man, Oscar Grant, who died on the Fruitvale BART Station platform on New Year's Day in 2009.
That ruling -- coupled with decisions that excluded witness testimony that the 911 caller had been harassing Smith and Appleton on the train -- prompted Adachi to launch an unsuccessful attempt to remove Judge Anne-Christine Massullo from the case. He accused the judge in a motion of bias, a move he conceded was "controversial."
"One of the first things that she did is excluded testimony of witnesses who would have said that Michael did nothing wrong in the train," he said. "I thought that was extremely unfair given, that she was going to allow the call made by the person who falsely accused Michael of attempting to commit a robbery and falsely having a weapon."
"The judge immediately said, 'I’m not going to let you talk about Black Lives Matter or the Oscar Grant case,' " Adachi said. "How do you talk about a case involving a young African-American man assaulted by BART police without talking about Oscar Grant, without talking about racial attitudes in America, particularly at this point in time?"
Stanford law professor Robert Weisberg said the context of race and policing impacted the case.
"This case sort of fell into the strike zone of a whole bunch of vectors in legal and police controversies in recent years," he said, noting that while the San Francisco Police Department was not involved in the case, the prolonged scrutiny on the city's police force was likely in the minds of jurors.
Like Adachi, Weisberg wondered whether an unconfirmed report that Smith may have had a gun should provoke a more subdued police response.
"We simply don’t know how careful the police were to confirm or disprove the allegation that Mr. Smith was carrying a weapon," Weisberg said. "All they knew is someone reported that. That gives them a pretty good reason to suspect the person has a weapon, but maybe not an automatic inference of it."
Adachi said the police's strong response to the call was beyond inappropriate, and the caller should be charged with making a false report.
"There’s a double standard that’s applied to police," he said. "There’s a double standard that’s applied based on race. What if the roles had been reversed? What if Michael Smith was the one that made a false allegation against a white man, and as a result the white man was taken down by police?"
A spokesman for the San Francisco District Attorney's Office said there was insufficient evidence to charge the caller.
BART maintains that police were using an appropriate amount of force, given Smith’s behavior and the report of a gun.
“It's just unfortunate that Mr. Smith didn't comply in the beginning, and this never would have happened,” said BART Deputy Police Chief Jeffrey Jennings.
A BART district spokeswoman said Friday that an "active internal affairs investigation" into the incident is ongoing, and that "there is nothing for us to add," about the end of Michael Smith's criminal trial.
A district attorney's spokesman said there is a "wide range of reasons" that the office would not purse a retrial in the case. He said the whole of the police body camera footage answers the question of why prosecutors charged the case to begin with and declined to elaborate. More video footage can be viewed here.