Years ago, there used to be restaurants which would advertise that they were "kosher style". That meant that the food was not kosher at all but rather kosher "style". Bnei Torah realized that that is a farce. The laws of the Torah are very detailed and if one of the necessary conditions is for kashrus is missing, it does not help that it is "kosher style"; it is absolutely not kosher.
The same is true in all areas of halacha. Halacha is very detailed and very complicated. Many non-observant Jews raise a question, "do you really think that G-d is so pedantic that He really cares about all of those intricate details??" Rav Soloveitchik zt"l once pointed out that the same G-d that gave the Torah also created all living creatures in the world. The DNA of a simple butterfly is extremely complicated. The same G-d who came up with the idea about complicated DNA also came up with all of the halachos, including all of their complicated details.
Every so often, Jewish folklore takes over a certain halacha and succeeds in totally distorting it, sometimes l'chumra and sometimes l'kula. The Torah tells us (Devarim 17:11) that when the rabbonim issue a psak, one is not permitted to ignore that psak by either going to the right or to the left - "לא תסור מן הדבר אשר יגידו לך ימין ושמאל". Some of the commentaries interpret that going to the right means l'chumra, that one feels that the rabbonim were too lenient; and going to the left means l'kula, that one feels that the rabbis were too stringent in their psak.
Over the years, folklore has taken over the laws of mesirah and misrepresented this halacha as if it implies that no Jewish criminals may be given over to the police. Those who follow the Daf Yomi have been learning the Gemorah Gittin the last three months. In the first perek in Gittin (7a), the Gemorah makes it clear that sometimes mesirah is permissible and even required. If one is a public menace, or one is harming other people, it is clear from the Shulchan Aruch and all of the classical poskim that there is no prohibition of mesirah and because the Jewish community in chutz la'aretz has no beis din which can take care of the matter, we have no choice other than to report the individual to the governmental authorities. Just the other day, I read a beautiful essay on this topic in a sefer called shu"t Ishei Yisroel (volume 6 page 522), by Rabbi Aschi Dick (a young talmid chacham who gives shiurim in the OU center in Jerusalem) which quotes all of the sources that indicate clearly that the prohibition of mesirah definitely does not apply in such a situation.
Let us not fall in to the "kosher style" attitude that used to be so prevalent in the area of kashrus years ago. All the details of every halacha are significant, folklore notwithstanding.