  We present a polarimetric investigation of the protoplanetary nebula Frosty
Leo performed with the Submillimeter Array. We were able to detect, in the low
continuum level (peak at 14.4 mJy beam$^{-1}$), a marginal polarization at
$\sim2.6\sigma$. The molecular line investigation based on the CO
$J=3\rightarrow2$ emission shows a peak emission of 68.1 Jy beam$^{-1}$ km
s$^{-1}$ and the polarization detection in this CO line is also marginal, with
a peak at $\sim3.8\sigma$. In both cases, it was therefore not possible to use
the electric vector maps (B-field) to accurately trace the magnetic field
(B-field) within the PPN. The spatio-kinematic modelling realised with the
different velocity channel maps indicates three main structures: a distorted
torus accompanied by a bipolar outflow or jet aligned with its axis and a
flattened spherical "cap". The comparison of the CO polarization segments with
our model suggests that the polarized emission probably arises in the first two
components.
