Smallville Season 4 Episode 9

How did Clark get the diamond earring from the elevator shaft? He might have used his super-powers but it would have been rather awkward even at superspeed.

The newspaper headline at the end says Lex was acquitted of a "double homicide." Professional newspapers use that term to refer to two murders that occured at the same time and place, not two murders spread out over several days and in different locations. Also, you can't be acquitted if you never go to trial.

Once again the penitentiary visiting system is unbelievably wide open considering convicted murderers are kept here (and a riot recently happened, in "Transference"). Plus, Clark gives Lionel the diamond earring. Visitors don't get to give imprisoned convicted murderers jewelry, even just to examine.

When Clark is telling Chloe about the car he had found at the hotel, Chloe is holding the newspaper. But in the next scene the paper is no longer in her hands and she later picks it up from a nearby table.

The alcohol fire is incorrect in several regards. Most spirits don't burn very well and those that do are not that clean. Alcohol/liquor fires are also nowhere near hot enough to do the amount of damage to the floor that we see after Clark leaves.

Lex's implants for cleaning his blood every 72 hours are missing when he is in the bed.

Lex comments that he never gets the names of the girls he sleeps with, and yet both Lex and Lionel send these girls diamond earrings by courier as a way of ending their "relationships". If they don't know these girls' names, then how do they find their addresses?

Once again we see that Clark has telescopic vision, although it has never been previously established or specifically stated in any way, shape, or form.

When Clark is in the barn towards the end he looks out into a clear sky, when the scene goes to Jason getting in the car its pouring rain out.

As is often the case, the whole legal situation is tossed out the window. Why would Clark knocking out the killer mean that Lex was cleared of all charges? Unless she was stupid enough to confess, or there was some inconvenient unmentioned evidence they don't bother to show the audience, the woman either would not be convicted of the murders (although she'd be in trouble for assault on Lex), or Lex would still be under suspicion. Nothing happens in the last few minutes of the episode to clear him of the charges, and yet they're inexplicably dropped.

The killer knocks out Lex, hard, by hitting him in the chin with a metal weapon. But when he wakes up three hours later, his chin is unmarked.