Not entirely sure what type of real estate law she is currently in, but one recommendation would be to work in renewable energy development. If she currently works in real estate transactions, there's probably a good amount of carry over, as renewable energy projects are tangible assets that generate long term cashflow (similar to an apartment building).

FWIW, in my experience (ASHRAE), the building standards are written by engineers without much input from lawyers.

I'm pretty sure LEED enforcement is actually a trademark issue (as LEED is just a private organization that allows buildings to use the LEED logo if they meet certain requirements). Enforcement of IBC/ASHRAE stuff is typically done at the county level - and the people who do that are not lawyers either, they're building inspectors.

Maybe look at public policy? Probably HUD or maybe DOE.

An experienced lawyer in real estate business looking to transition into green building standards can explore several career paths. Participating in career change programs, contributing to charter cities, and utilizing strategic abilities in Program Manager roles are viable options. Additionally, joining organizations like Union Developers, which focus on sustainable building, or exploring opportunities in the private sector with companies that prioritize sustainability, can be beneficial.