After more than four decades of public service to Wisconsin, Justice David Prosser announced Wednesday he will retire July 31.

According to a statement released by the Wisconsin Supreme Court, before becoming a justice, Prosser was a commissioner on the Wisconsin Tax Appeals Commission from 1997 to 1998 and a state representative from 1978 to 1996.

During his time as a representative, he served as speaker of the house for two years and minority leader for five years. After 18 years as a state representative, he became a Wisconsin Supreme Court justice, where he has served almost another 18 years.

Prosser said in a letter to Gov. Scott Walker working in all three branches of the government during his career was an “exceptional privilege.”

“Public service was the career I chose at an early age,” Prosser said. “That goal has been fulfilled.”

Walker said in a statement during Prosser’s time on the Supreme Court he demonstrated “his love for the law and commitment to Wisconsin’s citizens.” He said it was his pleasure to serve with Prosser while in the Assembly together and thanked him for his service to the state.

Jay Heck, Common Cause Wisconsin executive director, said Prosser’s retirement will cause a highly contested Supreme Court election early next year. Walker will have to appoint someone to fill Prosser’s vacant seat after July 31, Heck said.

Whoever is nominated, Heck said, will also have to stand for election again next year, in a race similar to the election between Supreme Court Justice Rebecca Bradley and Appeals Court Judge JoAnne Kloppenburg.

[UPDATED] Cruz, Sanders win Wisconsin primaryU.S. Sen. Ted Cruz, R-Texas, and U.S. Sen. Bernie Sanders, D-Vermont, won the Wisconsin primaries for their respective parties Tuesday Read…

In his letter to Walker, Prosser gave the governor advice for picking his successor.

“In choosing my successor, Governor, I respectfully request that you select a person who is fully committed to the important mission of the judiciary,” Prosser said. “Such a person will understand that promoting the reputation and integrity of the institution is more important than the promotion of any individual.”