Complex sentence: When Matthews is discovered to have been with another prostitute, LaGuerta initially tells Debra to cover it up, but when she continues to search and finds proof of Matthew's involvement, LaGuerta makes it clear that she will depose Debra if she steps out of line.
Split into simpler sentences: When Matthews is discovered to have been with another prostitute, LaGuerta initially tells Debra to cover it up. When Debra finds proof of Matthew's involvement, LaGuerta makes it clear that she will depose her if she steps out of line.