Your lease down payment is deducted over the life of the lease, per IRS publication 463.
From IRS publication 463:
Deductible payments. If you choose to use actual expenses, you can deduct the part of each lease payment that is for the use of the vehicle in your business. You can’t deduct any part of a lease payment that is for personal use of the vehicle, such as commuting.
You must spread any advance payments over the entire lease period. You can’t deduct any payments you make to buy a car, truck, or van even if the payments are called lease payments.