NEW YORK (CBSNewYork/AP) — Bronx District Attorney Robert Johnson said Friday that he wants to leave his post and be nominated to become a state Supreme Court judge.

In a statement Friday, Johnson said he has asked Bronx Democratic Chairman and state Assemblyman Marcos Crespo for the nomination.

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Johnson noted that he submitted his name for reelection as DA just this past spring, and said he has gained “tremendous satisfaction” from the position. Still, he said in the statement, it is time to move on.

“After much inner reflection, I have concluded that I would like to serve in another capacity. It is time for change in my life,” Johnson said in the statement. “The judicial position will allow me to make a career move that provides the change that I seek without giving up public service.”

Johnson also refuted claims that there was a political deal involved in his decision.

“Contrary to what has been reported, no one, including anyone associated with the Bronx Democratic Party, has ever offered me another position, nor has anyone asked me to step down or retire as the District Attorney,” he said in the statement. “I have, over the years, enjoyed their full faith and support both personally and through many electoral processes.”

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Johnson said he would need to be nominated during a political convention on Sept. 24. He says he will seek re-election as DA if he is not nominated to the judicial post.

Johnson has served as the Bronx County District Attorney since Jan. 1, 1989. He was the first African-American elected to be a DA in New York state, and has been the longest-serving Bronx County DA in history.

A Bronx native, Johnson has served as a judge before. He was appointed as a Criminal Court judge in 1986, and was promoted to be an acting justice on the Supreme Court before running for DA in 1988.

Crespo said in a statement that for Johnson to be on the ballot, delegates would need to choose him as their candidate at the upcoming political convention.

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