Many well-known leftists certainly have lied.
For instance, Chomsky has admitted to lying in order to protect dissidents from jail. And he further admits to life's little lies in _Understanding Power_. (Probably says you have to be a "crazy saint" if you haven't occasionally lied. For example, if someone looks bad in a dress, when there's no chance to change into something else, should the person's feelings necessarily be hurt in order to avoid lying?)
But with such ethical questions, it's understandable that people's opinions diverge...
Tayssir