Rabbinic orthodoxy and Karaite Judaism are in many ways mutually exclusive, since they deny each other's view on the Oral law and the Written law.
However, within the Oral Law/halachic system there is a method which does allow one to be a practicing Karaite.
This method or mechanism is the distinction that rabbinic halacha makes between Torah Law (D'oraita in Aramaic) and rabbinic law (D'rabbanan in Aramaic). When there is a conflict between rabbinic law and Torah law, the mechanism allows the individual, or compels him, to violate the rabbinic law and uphold the Torah law. For example, embarrassing a person is a violation of Torah law, and hence a rabbinic law which will cause embarrasment can be discarded, so as not to embarass someone else (or even oneself). Another example is honoring one's parents. If a rabbinic law will violate this torah commandment, then the rabbinic law should be discarded.
Now, the Karaite can learn to play this system (if necessary). There is a Torah commandment of Lo Tosifu - do not add! Rabbinic laws , by definition, will violate this Torah law. It is not only the Karaite's duty to discard rabbinic laws, it is also that of rabbinic Orthodoxy. Thus, even if a jew, whether orthododox or otherwise, consideres the possibilty of there being such a thing as "oral law" the oral law itself has a mechanism to reject the rabbinic law if it conflicts with the Torah.
