The third officer charged in the death of Freddie Gray is on trial, and he is the “center of the universe” for the entire case, a Baltimore attorney not involved in the case says.

Officer Caesar Goodson drove the police vehicle transporting Gray before his death and is accused of giving Gray a “rough ride.” Prosecutors are trying to prove Goodson drove dangerously enough to to cause Gray’s fatal injuries and thus warrants a criminal conviction. One Baltimore attorney says the whole case hinges on Goodson’s trial.

“If they can’t prove that they can’t prove anything,” attorney Steve Silverman told The Daily Caller News Foundation. “The whole point is they put him in the back of a paddy wagon and they roughed him up and that’s why he died. If you can’t even prove causation for the basic theory of the case for the driver of the vehicle and the injury then how can you prove all these ancillary officers did something wrong?”

“Goodson is the center of the universe when it comes to this case,” he added. “If they cant’ prove this case, I don’t know what they’re going to do.”

Of the two officers already tried, one was acquitted and the other will be tried again because of a mistrial.