They have experienced difficulty regarding the rates at which students receiving Federal Financial Aid graduate - i.e. their issues are based on low graduation rates and not based on being a diploma mill.
They have also received criticism for the large number of loan defaults, and lobbying to change how the loan default statistics are calculated to make their numbers look better (at least according to Frontline). Same program also mentioned private for-profit schools account for a quarter of all student aid in the country, a disproportionally high number since they are not a quarter of our schools.
Public universities have large numbers of lobbyists serving their interests as well.
UoP had about 400,000 students at the time the Frontline piece was produced - that's seven Ohio State Columbus's [http://www.osu.edu/osutoday/stuinfo.php] so number of schools is not perhaps the best measure.
Rightly or wrongly, because UoP has open enrollment they admit more students who are eligible for Federal Financial Aid than most schools because of the population they enroll.
And nothing in the Frontline piece accused UoP of being a diploma mill as was implied by the prior comment to which I responded. A criticism of their business model is a different indictment altogether.
They have experienced difficulty regarding the rates at which students receiving Federal Financial Aid graduate - i.e. their issues are based on low graduation rates and not based on being a diploma mill.
Disclosure: my spouse teaches for UoP part time.