Background: Standardized Letters of Evaluation (SLOEs) are an important part of resident selection in many specialties. Often written by a group, such letters may ask writers to rate applicants in different domains. Prior studies have noted inflated ratings; however, the degree to which individual institutions are "doves" (higher rating) or "hawks" (lower rating) is unclear. Objective: To characterize institutional SLOE rating distributions to inform readers and developers regarding potential threats to validity from disparate rating practices. Methods: Data from emergency medicine (EM) SLOEs between 2016 and 2021 were obtained from a national database. SLOEs from institutions with at least 10 letters per year in all years were included. Ratings on one element of the SLOE-the "global assessment of performance" item (Top 10%, Top Third, Middle Third, and Lower Third)-were analyzed numerically and stratified by predefined criteria for grading patterns (Extreme Dove, Dove, Neutral, Hawk, Extreme Hawk) and adherence to established guidelines (Very High, High, Neutral, Low, Very Low). Results: Of 40 286 SLOEs, 20 407 met inclusion criteria. Thirty-five to 50% of institutions displayed Neutral grading patterns across study years, with most other institutional patterns rated as Dove or Extreme Dove. Adherence to guidelines was mixed and fewer than half of institutions had Very High or High adherence each year. Most institutions underutilize the Lower Third rating. Conclusions: Despite explicit guidelines for the distribution of global assessment ratings in the EM SLOE, there is high variability in institutional rating practices.