Baseball bat

1x07 A Time to Hate  Directed by Deran Sarafian
 Written by Jan Oxenberg
 First Air Date : Sunday, 16 November 2003
 Flashback year : 1964 (39 years ago)
   

Lilly investigates the case of Daniel Holtz, a college baseball player who was found beaten to death in an alley behind a gay bar in 1964. Daniel's mother comes to Lilly in the hopes that his killer can be brought to justice before she dies. Lilly discovers the maltreatment gay victims received in the 60's, when her investigation discloses that it may have been a policeman's nightstick that made the lethal blows.

Lilly : You didn't know your son was gay?
Helen : I didn't wanna know. And now, much too late, I realize... that kept me from really knowing him.

3x04 Colors  Directed by Paris Barclay
 Written by Sean Whitesell
 First Air Date : Sunday, 16 October 2005
 Flashback year : 1945 (60 years ago)
   

Det. Rush re-opens the 1945 case of a baseball player, bludgeoned to death with his own bat.

It's only a game. Hit a ball and run around bags. Fun. But for kids. A man has a life to live.

6x20 Stealing Home  Directed by Kevin Bray
 Written by Danny Pino Elwood Reid
 First Air Date : Sunday, 12 April 2009
 Flashback year : 1999 (10 years ago)
   

The team looks into the murder of a former Cuban baseball star who escaped to the U.S. to provide for his family after the Cuban government fired him for talking to a U.S. sports agent. Meanwhile, the team plays their annual softball game.

What happens in Cuba stays with us.