The paper presents the results of the monitoring of St. Petersburg newspapers held in January-May 2015. The monitoring included qualitative and quantitative study of the content and evaluation of all the materials published in St. Petersburg newspapers. Special attention was given to such sections as Society, Politics, Law, Economy. The purpose of monitoring regional press was to detect errors or misstatements in the media sources, including online media. Semantic distortion was found in 204 publications. Violations of journalism ethics give rise to the problem of information distortion and, as a consequence, useless, poor-quality information deforms the reality communicated to the audience. Systematizing the violations of ethical principles of journalism give a clear picture of the present-day Russian mass media and open up the ways to improve self-regulatory mechanisms. The study reported here is unique as it is the first research focusing on ethical violations in Russian mass media. The results of the study are used as case studies to analyze ethical conflicts, as materials to promote professional standards for journalists investigating corruption schemes, etc. The monitoring data is included in the study that will be discussed at the permanent international seminar on the ethics of journalism Ethics of Mass Communication: Research in Russia and abroad. The first seminar was held on October 3-4, 2013 at the High School of Journalism and Mass Communications, St. Petersburg State University, with the support of the German House of Research and Innovation in Moscow and the Consulate General of Germany in St. Petersburg.