a normal subgroup $n$ of a group $g$ is said to be an $emph{omissible}$ subgroup of $g$ if it has the following property: whenever $xleq g$ is such that $g=xn$, then $g=x$. in this note we construct various groups $g$, each of which has an omissible subgroup $nneq 1$ such that $g/ncong sl_2(k)$ where $k$ is a field of positive characteristic.