Since 1990s thenumber ofclinical (practice)guidelines has rapidlybeen increasing.They are systematically developed statements to assist practitioners and patient decisions about appropriate health care for specific circumstances. They have no legalbinding force as theyaremainlyproduced bysome associations ofmedical researchersand practitioners. Nevertheless the growing use of guidelines in medical practiceemerges many problems from a legal point of view. In many medical malpracticelitigations it is important to determine the standard ofmedical care.Clinical guidelinesplays various roles in its determination.Generally,medical professionals refer them astheir shields while patients as their swords. This paper reviews two Judgments onShizuoka District Court, April 17, 2015 (The court of first instance) and on TokyoHigh Court, May 26, 2016 (The court of second instance). One of issues on courtproceedings is the evaluation on “Guideline for obstetrical critical hemorrhage”and itsapplication.