No. No. No. That's not how it works. The police do NOT have probable cause to arrest someone just because the person has been arrested before (even well over a dozen times). Nor can the police arrest someone for being a drug dealer. The police can only arrest someone if they have probable cause to believe that the person is committing, or has committed, a crime (e.g., that he was dealing drugs, or some other crime). They did not have that here.
You’re absolutely right, I worded that badly. What I was trying to get across was that it seems very possible that the police did have probable cause as this kid had a very long history of dealing drugs. I would assume they caught the kid doing it again. But we all know what happens when you assume... I am interested in seeing more details on this case. If the police are guilty then they’re guilty. This is a very sketchy situation. A young kid just doesn’t die of a broken back, even when riding in a van while not buckled in.
It looks like your "conscience" needs a better conscience to correct you.
From below "the Supreme Court found that flights relation to probable cause must 'be assessed in context with all of the circumstances surrounding it.'"
http://www.fedagent.com/case-law-updates/621-caselawupdate0927
According to the following the police may have recognized gray as a chronic offender. A look out called out that police were coming. And then Gray ran.
http://www.baltimoresun.com/news/maryland/baltimore-city/bs-md-gray-ticker-20150425-story.html#page=1
The convict was LEGALLY arrested, for cause. He was carrying a knife BANNED BY BALTIMORE CITY CODE. Maryland does NOT have a state-level knife law preemption law.
It has been reported that the officers observed Gray and another man in what looked like a drug transaction. In a case like that they do have the right to arrest someone who is attempting to flee. The other man also ran but got away.