  As is well known, the non-Gaussianity parameter $f_{_{\rm NL}}$, which is
often used to characterize the amplitude of the scalar bi-spectrum, can be
expressed completely in terms of the scalar spectral index $n_{\rm s}$ in the
squeezed limit, a relation that is referred to as the consistency condition.
This relation, while it is largely discussed in the context of slow roll
inflation, is actually expected to hold in any single field model of inflation,
irrespective of the dynamics of the underlying model, provided inflation occurs
on the attractor at late times. In this work, we explicitly examine the
validity of the consistency relation, analytically as well as numerically, away
from slow roll. Analytically, we first arrive at the relation in the simple
case of power law inflation. We also consider the non-trivial example of the
Starobinsky model involving a linear potential with a sudden change in its
slope (which leads to a brief period of fast roll), and establish the condition
completely analytically. We then numerically examine the validity of the
consistency relation in three inflationary models that lead to the following
features in the scalar power spectrum due to departures from slow roll: (i) a
sharp cut off at large scales, (ii) a burst of oscillations over an
intermediate range of scales, and (iii) small, but repeated, modulations
extending over a wide range of scales. It is important to note that it is
exactly such spectra that have been found to lead to an improved fit to the CMB
data, when compared to the more standard power law primordial spectra, by the
Planck team. We evaluate the scalar bi-spectrum for an arbitrary triangular
configuration of the wavenumbers in these inflationary models and explicitly
illustrate that, in the squeezed limit, the consistency condition is indeed
satisfied even in situations consisting of strong deviations from slow roll.
