... other people behaving badly at my home group?
Smile, and offer them a cup of tea.
But what if it's affecting other people?
Trust that, when the pain gets bad enough, they'll work their own programme.
But what if it's really upsetting me?
Use this as a great opportunity to work your programme.
But what about the newcomer?
They have a Higher Power, too, and more sense than you do.
But what if it's affecting the group?
Unlikely, and it'll probably blow over.
But what if it's really affecting the group?
See the previous answer.
But what if it's really really affecting the group?
Check with your Al-Anon sponsor, and, if indicated, bring it to the attention of a steering committee member (secretary, chair, treasurer, GSR).
What if I'm a steering committee member?
Bring it to the attention of the other steering committee members, and go with the majority. If it's split 50/50, err on the side of doing nothing plus watchful waiting.
What if another steering committee member is the origin of the bad behaviour?
Get together with the other steering committee members and address it. If that does not resolve it, refer the matter to the group, and watch as the group resolves it. Or not. In which case, you can either exercise tolerance, which solves the problem, or you can leave, which solves the problem.
There is no problem that cannot be solved by working the Twelve Step programme myself, and then filling in the cracks with Al-Anon cement.
And in the meantime read this.