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We perform consistent reductions and measurements for three ultra-faint dwarfgalaxies (UFDs): Bo\"otes I, Leo IV and Leo V. Using the public archival datafrom the GIRAFFE spectrograph on the Very Large Telescope (VLT), we locate newmembers and provide refined measurements of physical parameters for these dwarfgalaxies. We identify nine new Leo IV members and four new Leo V members, andperform a comparative analysis of previously discovered members. Additionally,we identify one new binary star in both Leo IV and Leo V. After removing binarystars, we recalculate the velocity dispersions of Bo\"otes I and Leo IV to be5.1$^{+0.7}_{-0.8}$ and 3.4$^{+1.3}_{-0.9}$ km s$^{-1}$, respectively; We donot resolve the Leo V velocity dispersion. We identify a weak velocity gradientin Leo V that is $\sim$4$\times$ smaller than the previously calculatedgradient and that has a corresponding position angle which differs from theliterature value by $\sim$120 deg. Combining the VLT data with previousliterature, we re-analyze the Bo\"otes I metallicity distribution function andfind that a model including infall of pristine gas while Bo\"otes I was formingstars best fits the data. Our analysis of Leo IV, Leo V and other UFDs willenhance our understanding of these enigmatic stellar populations and contributeto future dark matter studies. This is the first in a series of papersexamining thirteen UDFs observed with VLT/GIRAFFE between 2009 and 2017.Similar analyses of the remaining ten UFDs will be presented in forthcomingpapers.

VLT Spectroscopy of Ultra-Faint Dwarf Galaxies. 1. Bo\"otes I, Leo IV, Leo V