OPELIKA, Ala. — At times in a courtroom here on Tuesday, as when a prosecutor and a defense lawyer spoke about Heisman Trophy winners and a revered college football coach, it was nearly possible to forget that the defendant is considered by many to be the most powerful man in Alabama.

But over a dizzying day of numbers and names, and after months of intrigue and scandal that could plunge Alabama government into chaos, a jury received its first collective glimpse at the cultivation and use of political clout in this state as Michael G. Hubbard, the speaker of the state House of Representatives, went on trial on 23 felony ethics violations.

“He just didn’t want to obey,” Matt Hart, a prosecutor, said here in Lee County, where a grand jury indicted Mr. Hubbard, a Republican, in October 2014. “He just didn’t want to be held accountable to the law.”

Much of what Mr. Hubbard did to draw the attention of prosecutors, such as steering Republican Party money to his printing business, is not in substantial dispute. But a lawyer for Mr. Hubbard, who is also accused of soliciting contracts and clients from people with interests before the state, said that he had acted within the limits of the ethics statute he helped strengthen as House speaker.