After five weeks of trial and 56 witnesses, few legal observers believed prosecutors came close to proving Sanford, Fla., neighborhood watchman George Zimmerman committed second-degree murder when he shot and killed Trayvon Martin in February 2012.

So for many legal analysts, it was no surprise that jurors rejected even a lesser “compromise” verdict of manslaughter, acquitting Zimmerman outright of all criminal charges and deciding he acted in a reasonable way to protect his own life.

The acquittal was a stinging blow for prosecutors and their decision to file the second-degree murder charge against Zimmerman, who was not ­initially arrested by ­Sanford police after claiming self-defense. And it was a resounding embrace of the defense’s strategy during closing arguments not just to establish that prosecutors hadn’t proven Zimmerman guilty, but also to show he was “absolutely” innocent.

“The jury clearly believed that you have a right to defend yourself,” said Jude Faccidomo, the former president of Miami’s Florida Association of Criminal Defense ­Lawyers. “Especially when cases are so gray, like this one was, self-defense really resonates because ­ people can associate with being afraid.”

And while some also have questioned the state attorney’s acceptance of a mostly white jury, a more diverse panel would have returned the same verdict, lawyers who have watched the case believe.

“After seeing the quality of the evidence presented by the state, the diversity of the jury really didn’t matter in the end,” said Larry Handfield, a prominent black Miami criminal defense lawyer. “But it would have helped the community in giving more credibility to the decision to acquit ­Zimmerman.”

A look at the evidence shows why the jury rejected the state’s case. For prosecutors intent on proving the more serious charge, proving the “ill will,” “hatred” or “spite” needed to convict on second-degree murder hinged on painting Zimmerman as a frustrated, would-be cop fed up with intruders in his gated Sanford community.

To do so, they focused on Zimmerman’s past — over defense objections — introducing evidence of his interest in law enforcement, including a ride-along with Sanford police, a class on criminal justice, an unsuccessful application to a Virginia police department.

Prosecutors also played five calls to police that Zimmerman made in the several months before the shooting, in an attempt to show a pattern of “profiling.”

Their most important evidence to prove “ill will” was his call to a police nonemergency dispatcher when he first spotted Martin and muttered obscenities about punks that always get away. “If there was ever a window into that man’s soul, it was that defendant’s words on that phone call,” prosecutor John Guy said in a poignant closing argument,

Zimmerman’s prosecution was made tougher under Florida’s 2005 Stand Your Ground law, which eliminated a citizen’s “duty to retreat” before using lethal force in the face of a deadly threat — an instruction given to jurors on Friday.