This morning, Fox & Friends hosted a segment on the effects of Prince William County, Virginia's “strict immigration enforcement policy,” by cherry-picking from a recently released report on the policy to claim that it has worked to reduce crime because of a reduction in reported assaults and hit-and-runs.

However, the study itself concluded that “we find that the policy has not affected most types of crime in Prince William County, in large part because illegal immigrants account for only a small percent of arrests overall and a small to modest share of offenders for most types of crime.” They go on to note that about 70% of “arrests of illegal immigrants were for just three specific offenses: public drunkenness, driving while intoxicated, and driving without a license.” They also “caution” that “some of” the drop in assault rates “may also have been due to a reduction in reporting of assaults by illegal immigrants (and perhaps legal immigrants as well).

The county's ordinance was passed in 2007 (and later modified in 2008), and it directs County Police Officers, when they arrest people, to “inquire into the citizenship or immigration status of the detained person if there is probably cause to believe such person is in violation of federal immigration law and when such inquiry will not expand the duration of the detention.” Despite having operated quietly for a number of years, the ordinance gained national prominence last summer due to its similarity to the Arizona immigration law SB1070.

Last June, Fox & Friends advanced the false claim that the ordinance lowered crime rates. We noted at the time, that Doocy was selectively picking statistics to boost the ordinance, and that violent crime had increased while, according to a University of Virginia study, "[T]he policy has not reduced most forms of crime in PWC." Recently, a new study came out, evaluating the policy's effects on crime rates in 2010. Fox & Friends was on the case, reliving their previous set of falsehoods:

Fox & Friends again selectively picked data to support their claim. The study did note a decrease in certain crime rates, but unmentioned by the hosts was that “most types of serious and minor crime did not decline (or increase) following the policy's announcement in July 2007 or its implementation in March 2008.” Further, the study made clear that there were major caveats:

Our conclusions about the policy's impact on crime must be cautious, due in large part to the lack of historical, pre-policy data on crimes committed by illegal immigrants. Our investigation of data from several sources suggests that the immigration enforcement policy has not affected most forms of crime in PWC. Overall, illegal immigrants currently make up a relatively small proportion of arrestees for serious crimes, and a substantial majority of arrested illegal immigrants are charged with traffic offenses or misdemeanors, particularly public drunkenness, driving without a license, and DUI, which together account for 70 percent of their arrests. Given the lack of pre-policy data on arrests of illegal immigrants, we cannot determine whether or not those proportions have changed since the policy's implementation.

The study's authors also “caution[ed] that some of this drop may also have been due to a reduction in reporting of assaults by illegal immigrants (and perhaps legal immigrants as well.”

The hosts of Fox & Friends never managed to mention either any of the study's findings that contradicted their pre-determined support of the ordinance, nor the note of caution stressed by the study's authors.