We present a new method of time-resolved Mueller matrix imaging polarimetry for spatial and temporal characterization of the polarization effects in backscattering from turbid media. The technique allows measuring the time evolution of spatially varying polarization patterns of diffusely backscattered light with picosecond resolution. A series of time-resolved polarization patterns are obtained at various time delays, are analyzed in sequence, and used to separate the polarimetric contributions of different scattering paths. Specific features of the 2D Mueller matrix components corresponding to light backscattered from colloidal suspensions were determined and characterized. The temporally-and spatially-resolved measurements permit detailed analysis of the changes in the magnitude, sign, and the general symmetry properties of Mueller matrix components.