The president wants to give 401(k) savers access to alternative assets, but lawyers say executive power has limits.

New rule opens 401(k) plans to private equity, prompting debate over benefits versus costs and transparency risks.

The move is a critical step in President Donald Trump’s push to open 401ks — the term for US retirement savings accounts — to private investment firms who see the system as a crucial market to draw in assets, particularly as large pensions and endowments pull back.