When his 17-year-old son got home from school one afternoon last week, Richard Claytor met him at the door with the soberest of looks on his face.

“He thought he was in some kind of trouble,’’ Claytor said with a wry chuckle. “And I thought about calling his bluff and waiting to see if he admitted to anything, but I thought better of it. My kid’s not a trouble maker or a troubled kid. We just needed to get ‘the talk’ out of the way.’’

Claytor, a nationally renowned parenting consultant and director of the state’s Fatherhood Initiative, a program aimed at helping single and divorced fathers stay involved in their children’s lives, said the shooting death of Florida teenager Trayvon Martin is prompting some black parents, especially fathers, to revive a talk they had hoped they would not have to have with their sons, not the talk about sex or curfew or texting-while-driving, but the one about “proper’’ carriage in the presence of police officers and other authority figures. It is a talk that historians say has very long roots, dating to the Civil War era.

Martin, a 17-year-old from the Miami area, was killed Feb. 26 by a neighborhood watch volunteer. Walking home from a convenience store, the teenager was unarmed when George Zimmerman spotted him, called police and described Martin as suspicious and began to follow him. Zimmerman, who has not been arrested or charged with a crime, told authorities he had to shoot because Martin had attacked him, unprovoked.

“It’s an old story, an old fear,’’ said Claytor, who also volunteers as a moderator for support groups for married fathers.

“And the feeling I got, and anecdotally I can say many black fathers got, was a cold chill, because if an unarmed kid, dressed as most athletic teenage boys dress, looks suspicious, then what about my boy?’’