All the speculation about Bob Rae becoming leader of the Liberal Party glossed over a minor technicality that hitherto kept him from entering the race: not actually being a card-carrying member of the Liberal Party.
Fortunately, he's having that little problem fixed.
People are rightly upset about outside opportunists trying to take over the leadership of parties with which they have had no real and substantial previous connection. David Orchard comes to mind as the most egregious example thereof, but the Liberal Party is full of many more such examples.
Perhaps parties should require a minimum length of membership before seeking the leadership thereof (excepting, of course, newly-founded parties.) Five years seems like a reasonable length of time, as it will force leadership contenders to commit to a party during the length of one normal election and government cycle, through its ups and downs.
It would also prevent hijackers from trying to take over; they would have a far more difficult time of it, as few have the patience, support and resources to run protracted stealth campaigns.
And it would force parties to resist the temptation to bring in the "man on a white horse" from outside.
But this is a matter for parties to decide for themselves as an internal matter, not for Parliament or Elections Canada to determine. Parties are the best judges of how to manage their own internal affairs.