  In recent years, fundamental relationships for the black hole X-ray binaries
have been established between their X-ray luminosity $L_X$ and the photon index
$\Gamma$ of their X-ray spectrum. For the moderate-luminosity regime, an
anti-correlation between $\Gamma$ and $L_X$ has been observed. In this article,
aimed to verify if the moderate luminous X-ray binary system LSI +61303 is a
black hole, we analyse $Swift$ observations of LSI +61303. We compare the
derived $L_X$ vs $\Gamma$ distribution, first with the statistical trend for
black hole X-ray binaries, then with the trend of the pulsar PSR B1259-63, and
finally with the individual trends of the black hole X-ray binaries Swift
J1357.2-0933 and V404 Cygni. We find that the system PSR B1259-63 shows a
positive correlation between $\Gamma$ and $L_X$, whereas in contrast LSI +61303
shows the same anti-correlation as for black hole X-ray binaries. Moreover, the
trend of LSI +61303 in the $L_X$/$L_{Eddington} - \Gamma$ plane overlaps with
that of the two black holes Swift J1357.2-0933 and V404 Cygni. All three
systems, Swift J1357.2-0933, V404 Cygni and LSI +61303 well trace the last part
of the evolution of accreting black holes at moderate-luminosity until their
drop to quiescence.
