Where I live the only way you can force someone into treatment is if they are proven, without a doubt, dangerous and then either the police or a doctor can do it. However, if you are forcing them into treatment of any sort....and they arent going on their own free will...there is a good chance it is a waste. My sister is a crack addict who suffers from bipolar, kleptomania, narcassism and depression. She was forced into treatment by the courts and it was an utter fail. She eventually went on her own free will with better results.

In my state, county etc...if someone threatens others or theirselves safety they can be committed (by calling 911 and an ambulance etc) for an observation...the longest one I know of was 7 days, and they let him out after 4...You should check with your town...
the other thing about this is that if the person is violent or armed, there can be some pretty serious unintentioned by products such as legal charges, and/or violence from the people taking them for help (ie fighting to get someone under control)
Scary any way you look at it.
But, if they or you are in danger...call. they are the professionals.

I went through this with my son in January and it is very frustrating. My son had just turned 18 so as his parents we no longer had any say in his medical care however when he became delusional we did have him hospitalized because we were able to trick him peacefully to the E.R. where a doctor saw firsthand his hallucinations. I was reluctant to call the police because as Blue stated if things went wrong I didn't want him facing charges luckily everything went well and he recovered after being in the psychiatric ward for 5 days.It is a very hard situation but if you feel they are a danger to themselves or others call 911 Hang in there!

Thanks for your responses i am trying to look up somethings now and my sister is not willing at all because she thinks that she is fine, but it would be best for her and her children if she got the help she needs. I'm just afraid if i call 911 and she starts to act crazy that things might get pretty bad and another thing is that she can be "normal" sometimes when she is not high or drunk so she might be able to talk her way out of going into a psychiatric ward...this really sucks i hope one day there will be way more out there to help addicts because in NYC i dont see a lot of options.

I know in TX, you can gain a mental health warrant for someone who is at risk of harming themselves or others, & the police will take them to a hospital...