I think it means someone who is sort of like a 'fall guy',that others blame things on.Someone who doesn't have a real dominant personality and that can be taken advantage of.
A sucker. A person who is made fun of, the butt of a joke, etc. And as kim said, it can also mean scapegoat.
NOUN:
Slang pl. pat·sies
A person easily taken advantage of, cheated, blamed, or ridiculed.
a wet noodle, wimp..the person everyone picks on...etc
Some one who is put in the position of being ignorant to the bad things going on around them.
They say Lee Harvey Oswald was a patsy.
I think I know the commercial your thinking of. It's a play on words. The mother's name is Patsy and she''s doing crazy things checking her kids for drugs. I love that commercial , funny.
a patsy is an addicts dream, someone who will continue to enable us, even if they know they really shouldn't. people often forget to mention thast every addict has someone who enables them, someone who will continue to look the other way. and this is usually the first bridge we have to burn in order to succeed.