This article contains so many arithmetic errors, impossibilities, and faulty assumptions that its entire validity should be questioned.  Ms. Schurman-Kauflin should be embarrassed to have published such a shoddy paper.


"When examining ICE reports and public records, it is consistent to find sex offenders comprising 2% of illegals apprehended.  Based on this 2% figure, there are approximately 240,000 illegal immigrant sex offenders in the United States."  The 2% figure is undocumented.  It is incorrect to assume that, because 2% of those arrested were sex offenders, 2% of the entire population must be sex offenders as well.  It would be equivalent to saying that, because 100% of those incarcerated were found to be criminals, everyone else must be a criminal, too.


"This translates to 93 sex offenders ... coming across U.S. borders illegally per day."  That would make 33,945 per year.  If that is 2% of the total, as is claimed, then 1.7 million illegal immigrants would have to be entering the US each year.  However, a report from the nonpartisan Pew Hispanic Center found that the number of illegal immigrants entering the United States has declined from an average of 800,000 a year in 2000-04 to 500,000 a year in 2005-08.  Thus, this article must be exaggerating by a factor of 3.


"Gang rape took place in .007% of the cases."  1500 x .007% = 0.105, a tenth of a case?  This does not make sense.


"Serial rapists accounted for 3% of all illegal immigrant rapists ... with the number of victims ranging from 2 to 11."  Obviously, their definition of "serial" is "more than one."  This means that the other 97% (347 offenders) raped only once, which is inconsistent with the claim that "each sex offender averaged 4 victims."


"Serial killers accounted for .005% of the sex crimes. The serial killers averaged 9 victims per offender."  If there were just one serial killer who had nine victims, that would mean that there had to have been 180,000 sex crimes in the study (180,000 x .005% = 9), 120 crimes per offender, and 30 crimes per victim - ridiculous numbers.  It just gets worse with more than one serial killer.


"The average age of illegal immigrants who were sex offenders was 27.  Child molesters (525) averaged age 32, the average age of rapists (358) was 26, and murderers (617) averaged age 28."  The average calculates out to be 29, not 27.


Regarding all of the statistics cited in the article, no comparison is made to the population of the United States as a whole.  It is therefore valid to question the relevance of all of this information.