Back in 2014, there was a fight between Ben Mitchell and Lee. Lee continued to batter Ben long after it had become clear that Ben had had enough.
It was followed by a scene in which, back at the Queen Vic, Lee broke down, speaking to his mother about an incident from his army days in which he was in a fight with another soldier. The red mist has descended and Lee had almost killed the other soldier.
I think that it is a safe bet that Lee's current storyline is heading towards a confrontation between Lee and Oz that results in the manslaughter of Oz.