There was a moment of levity in a tense committee meeting at the statehouse, and a former football star accused of killing his wife provided the fodder. The House Public Safety Committee met for several hours yesterday, discussing a bill that tries to make it harder to get the main ingredient that those who “cook” the illegal drug meth need. At one point, a frustrated Representative — Lance Horbach of Tama — created a bit of theater. Horbach reached under the table to get a cardboard box. It was full of packets of cold medication that contain pseudoephedrine, stuff he bought on the Internet. He dumped it all on the table, and then tossed a bit of it around — all of his actions captured by the four television cameras in the room. Hours later, Representative Jim Van Fossen, a retired cop from Davenport, drew the only round of laughter in the committee yesterday when he referred to Horbach’s stunt as “doing an O.J.” — a reference to the much-watched O.J. Simpson trial.