Is there an error in this sentence "A crocodile was supposed to weep as it devoured it's prey insincere crying is referred to as 'crocodile tears'

Yes, there is an error.

The error is the use of the pronoun "It's" instead of "its"

Explanation:

Here's the sentence: "A crocodile was supposed to weep as it devoured it's prey insincere crying is referred to as 'crocodile tears'

The pronoun "It's" means "it is" and it is wrong in the context used.

John Proctor's supporters and friends were George Jacobs, Martha Carrier and John Willard.

I hope this helps, L.E.