For William M. Libit, an affinity group for LGBT employees at his law firm allows him to meet attorneys and staff and find ways to help them grow professionally. “We recognize we’re a professional-services firm, and people are our most important asset,” said the chief operating partner at Chapman and Cutler LLP. “We believe in recruiting the best talent, regardless of race, gender or sexual orientation.” That philosophy of inclusiveness is one of the reasons Chapman and 12 other law …