NASHVILLE (AP) — Robert O'Connell, the executive director of the Tennessee State Employees Association, has announced he plans to retire in May after four years leading the group.

O'Connell has run the TSEA amid successful efforts by Republican Gov. Bill Haslam to overhaul state civil service rules that make it easier for executive branch employees to be hired and fired, and allow merit raises for high-performing workers and pay decreases for poor ones.

But sponsors noted when the law was enacted in 2012 that negotiations with the TSEA had resulted in about 20 changes to the original bill, including that seniority will remain a factor in making decisions on staffing changes.

O'Connell was the association's attorney before he became executive director.