We present the results of K-band imaging polarimetry of three radio galaxies,
including the very red and apparently old z=1.55 galaxy 53W091. We find weak
evidence for polarization in components of 3C 441 and in the south-east
companion of 53W091, but no evidence of significant polarization in 53W091
itself. We also find strong evidence that MRC 0156-252 is unpolarised. We
present upper limits for the K-band polarization of all three sources. For
53W091, the lack of significant K-band polarization provides further confidence
that its red R-K colour can be attributed to a mature stellar population,
consistent with the detailed analyses of its ultraviolet spectral-energy
distribution which indicate a minimum age of 2-3.5 Gyr.Comment: 7 pages, 3 postscript figures. In press at MNRA
