Since someone applying at MEPS isn't even in the military, obviously the military would have no authority to punish someone for anything. Until the contract is signed, the person isn't under the UCMJ.
No, it isn't "one big test of how well you can lie." :roll:
The person volunteering has to provide various documents, take a battery of written tests, get physically examined, have a urinalysis done, and have a background check done.