Freddie Gray, 25, should be alive today, but he isn’t. He died on Sunday morning from a broken neck that he sustained during an encounter with Baltimore police a week earlier. The Guardian reports,

Gray, 25, died on Sunday morning, a week after he was chased and arrested by officers on bicycles on Baltimore’s west side. Police have refused to disclose the alleged violation for which Gray, who was black, was stopped. His family said he was not charged with any crime. However a court filing from the day of his arrest, in which Gray’s name was spelled incorrectly, suggested he was charged with illegally carrying a knife.

Cellphone video recorded at the scene showed Gray shouting and moving his head as he was carried into a police van. Yet he was later found to have suffered three broken vertebrae. Gray lapsed into a coma and was brought back from the verge of death, before undergoing extensive surgery and eventually being declared dead on Sunday.

Baltimore Mayor Stephanie Rawlings-Blake announced at a press conference yesterday that the city has placed the four police officers who arrested him on administrative leave and officially commenced an investigation to determine what happened.

Let’s briefly review the legal rules that apply to investigatory stops:

1) No rule prevents police officers from contacting a citizen in a public place, such as a public park or city street, to engage him in conversation.

2) If the officers identified a set of articulable facts and circumstances that supported a reasonable suspicion that Mr. Gray was committing a crime, they could detain him for a limited period of time to investigate further.

The police have not stated why they attempted to detain him. Therefore, subject to the receipt of additional information, it appears that they lacked a reasonable suspicion to believe he was committing a crime and they should have let him go. Instead, they arrested him.

We do not know when or how Mr. Gray fractured three vertebrae in his neck. The fractures were severe and likely his death.

3) Police may use reasonable force to stop a person attempting to flee, provided they have a reasonable suspicion that the person was committing a crime. Three vertebrae, each fractured by approximately 80%, suggests that police used excessive force to detain him.

In conclusion, police appear to have acted unlawfully..

Mr. Gray’s arrest happened less than a month after Officer Michael Slagle shot and killed Walter Scott in Charleston, SC.