If CONSTITUTION USA with Peter Sagal (8 p.m., PBS/Ch. 7) seems a little light, a little entertaining, well, that's a good thing.We live in a nation where 62 percent of the citizens can't tell you what the three branches of government are, but they yell about the rights they think they have under the Constitution. So I'm OK with anything that teaches people about the document.And Sagal (the host of "Wait, Wait ... Don't Tell Me" on NPR) does the job in an interesting, entertaining way.Elsewhere on TV ...NCIS (7 p.m., CBS/Ch. 2): Is a petty officer paranoid or is he really being followed?Splash (7 p.m., ABC/Ch. 4): Somebody is declared the winner in the finale of this dopey show.The Voice (7 p.m., NBC/Ch. 5): Contestants perform in a "live" episode. (Tape-delayed in this time zone.)NCIS: Los Angeles (8 p.m., CBS/Ch. 2): The team tracks a notorious arms dealer.Hart of Dixie (8 p.m., CW/Ch. 30): On a flight to New York, Zoe has to deal with a medical emergency. (Season finale)Dancing with the Stars (8 p.m., ABC/Ch. 4): Another pair is eliminated.New Girl (8 p.m., Fox/Ch. 13): Jess' dad stops by unannounced.The Mindy Project (8:30 p.m., Fox/Ch. 13): Mindy goes to a frat party.Golden Boy (9 p.m., CBS/Ch. 2): The deputy mayor was the last client to visit a murdered call girl.Body of Proof (9 p.m., ABC/Ch. 4): A gunman causes a deadly plane crash.Grimm (9 p.m., NBC/Ch. 5): A wesen has the ability to influence people.Independent Lens (11 p.m., PBS/Ch. 7): An older white man finds a Chinese bride online in "Seeking Asian Female."