This summary is not the rule. The rule text controls.
If someone in a criminal case needs help understanding English, or has a hearing or speech disability, the court can bring in an interpreter to help them. This makes sure everyone involved, including the defendant, witnesses, or other people in the case, can understand what's happening and communicate clearly during court proceedings.
The rules for how interpreters are chosen and paid for come from a separate court rule, Tennessee Supreme Court Rule 42. That rule spells out how interpreters get appointed and covers most of the payment details. If there are any interpreter costs that Rule 42 doesn't already cover, those costs get added to the regular court costs in the case.
In short, this rule makes sure people who need language help can get it, and it points to another rule for the specific details on picking an interpreter and paying for their services.