UPDATED | October 15, 2015 2:45 PM

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AUSTIN (CBSDFW.COM/AP) — The top education official in Texas plans to step down after the end of the year. According to a letter, Michael Williams says he wants to spend more time with his wife, at their home about 200 miles away from the capital.

Texas Education Commissioner Williams informed Governor Greg Abbott of his resignation, which is effective Jan. 1. Since joining state government more than 16 years ago, he’s been commuting weekends to be with his wife in Arlington, he said in the letter.

“It is finally time to head home,” he said.

Then-Governor Rick Perry appointed Williams in 2012 to lead the Texas Education Agency, which oversees the state’s 1,200 school districts and charter schools.

Williams made news shortly after taking office by temporarily suspending a rule that made the state’s standardized tests a vital component of high school students’ final grades. That rule was later scrapped. He also stressed the need to close achievement gaps between minority students and whites.

His resignation comes at a time when the agency is still involved in a 3-year-old school finance case. The Texas Supreme Court heard oral arguments last month in the case, which hinges on the cutting of $5.4 billion from classrooms in 2011 by lawmakers — funding levels that haven’t been restored in the subsequent two legislative sessions.

Before Williams became education commissioner, he worked for the U.S. Department of Education under President George H.W. Bush. He also previously served on the Texas Railroad Commission, joining the oil and gas regulatory panel in 1998. He left the commission in 2011 and mulled a run for the seat of retiring U.S. Sen. Kay Bailey Hutchison — but instead became one of 10 Republicans vying for the nomination in the 25th Congressional District. He ultimately lost that race.

Williams was the first African American to be named the state’s education commissioner.

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