Q:

Phrase "get blamed on"

Excerpted from The New Yorker:

Melodramatic or banal prose mostly gets blamed on the author, reasonably enough.

Something gets blamed means someone blames that something, and someone blamed on something means something is being blamed by that someone, but what is get blamed on?

A:

Blame as a verb assigns responsibility to an agent for a deplorable fact or act. There are two different constructions:
1) with the agent as direct object and the fact or act as object of the  preposition for

He blames her for his brother's death.
  He blames her for betraying his brother. 

2) with the fact or act as direct object and the agent as object of the preposition on

He blames his brother's death on her.
  He blames his brother's betrayal on her.

In the passive, you re-cast the active direct object as the subject, so with blame the construction you use is the one in which your subject is the active direct object. In your example, the subject is the deplorable fact melodramatic or banal prose, so you use the on construction.

We blame melodramatic or banal prose on the author.  →
  Melodramatic or banal prose gets blamed on the author.  

The first part of this answer is quoted from my Answer to an earlier question here.

A:

Ditransitive verbs (those which normally have a direct and an indirect object) often have two different passives. So "I gave John the book" has passives "The book was given to John [by me]" and "John was given the book [by me]".
In the case of "blame", the prepositions used are anomalous:

John blames me for the trouble.
I was blamed [by John] for the trouble.

but

The trouble was blamed on me [by John].

Colloquially, we often use forms of "get" for passives instead of forms of "be". 
So 

Melodramatic or banal prose ... gets blamed on the author

is a passive of 

[Somebody] blames the author for melodramatic or banal prose. 

