Among other things, some House Republicans want to impeach Rod Rosenstein for something that happened six months before he took office. 
.. and for something that happened both before Rosenstein took office *and* is belied by the declassified portions of the government's FISA application.
... and for "unnecessary redactions."
House Republicans also want to impeach Rosenstein for appointing Mueller, basically re-hashing an argument that's now been rejected by two federal judges (including one who's seen the classified memo outlining the scope of the special counsel investigation).
They also want to impeach him because they have concerns about the government's basis for alleging "collusion" between Russia and Trump, which isn't something DOJ has done.
They also want to impeach him for the "potentially improper authorization" of FISA searches of the Trump campaign. Page left the campaign a month before the FBI got its wiretap order; by the time Rosenstein took office the campaign was over.
And they want to impeach Rosenstein because he did not recuse himself from Congress' investigation of the Russia investigation.
This is a fascinating document -> assets.documentcloud.org/documents/4618…
