SB1137, Arizona
This bill was signed by the Governor on April 12. I have linked to the House summary of the bill rather than the text because it is easier to understand the significance of the measure this way. As the summary says, "Current law requires that in order to challenge the validity of any corporate action, the corporation’s membership must obtain at least 10 per cent of the voting members or at least 50 members (unless fewer are provided for in the articles of incorporation). SB 1137 establishes a separate statutory provision applicable to HOAs that proposes to allow an HOA member to challenge the corporation’s power to act." In other words, now a single member of an HOA can challenge board decisions.