As discussed in Note 1, the Company began operating in compliance with REIT requirements for federal income tax purposes effective January 1, 2013. As a REIT, the Company must distribute at least 90 percent of its taxable income (including dividends paid to it by its TRSs) and will not pay federal income taxes on the amount distributed to its stockholders. In addition, the Company must meet a number of other organizational and operational requirements. It is currently management's intention to adhere to these requirements and maintain the Company's REIT status. Most states where CoreCivic holds investments in real estate conform to the federal rules recognizing REITs. Certain subsidiaries have made an election with the Company to be treated as TRSs in conjunction with the Company's REIT election; the TRS elections permit CoreCivic to engage in certain business activities in which the REIT may not engage directly. A TRS is subject to federal and state income taxes on the income from these activities and therefore, CoreCivic includes a provision for taxes in its consolidated financial statements.

The TCJA was enacted on December 22, 2017. The TCJA reduces the U.S. federal corporate tax rate from 35% to 21%, requires companies to pay a one-time transition tax on earnings of certain foreign subsidiaries that were previously tax deferred, and creates new taxes on certain foreign-sourced earnings. However, the TCJA does not change the dividends paid deduction applicable to REITs and, therefore, CoreCivic generally will not be subject to federal income taxes on the Company's REIT taxable income and gains that it distributes to its stockholders. In the fourth quarter of 2017, the Company recorded, in accordance with ASC 740, the tax effects of enactment of the TCJA on existing deferred tax balances and there was no one-time transition tax on foreign earnings. The Company re-measured certain deferred tax assets and liabilities based on the rates at which they are expected to reverse in the future, which is generally 21%. In the fourth quarter of 2017, the Company recognized a charge of $4.5 million, which was included as a component of income tax expense, for the revaluation of deferred tax assets and liabilities and other taxes associated with the TCJA. CoreCivic applied the guidance in the SEC Staff Accounting Bulletin 118, "Income Tax Accounting Implications of the Tax Cuts and Jobs Act" when accounting for the enactment-date effects of the TCJA in 2017 and throughout 2018. At December 31 2017, the Company had not completed its accounting for all of the enactment-date income tax effects of the TCJA under ASC 740 for the following aspects: re-measurement of deferred tax assets and liabilities, one-time transition tax, and tax on global intangible low-taxed income. During the third quarter of 2018, the Company revised its estimates of the revaluation of deferred tax assets and liabilities resulting in the recognition of an additional charge of $1.0 million, which also was included as a component of income tax expense. At December 31 2018, the Company has completed its accounting for all of the enactment-date income tax effects of the TCJA.

	For the Years Ended December 31,
	2018			2017			2016
Current income tax expense
Federal	$	10,481		$	10,202		$	10,181
State		2,308			2,788			1,983
		12,789			12,990			12,164
Deferred income tax expense (benefit)
Federal		(3,422	)		1,088			(3,400	)
State		(1,014	)		(167	)		(511	)
		(4,436	)		921			(3,911	)
Income tax expense	$	8,353		$	13,911		$	8,253

Significant components of CoreCivic's deferred tax assets and liabilities as of December 31, 2018 and 2017, are as follows (in thousands):

	December 31,
	2018			2017
Noncurrent deferred tax assets:
Asset reserves and liabilities not yet deductible for tax	$	21,742		$	19,045
Tax over book basis of certain assets		1,665			40
Net operating loss and tax credit carryforwards		5,483			5,040
Intangible contract value		148			—
Other		123			172
Total noncurrent deferred tax assets		29,161			24,297
Less valuation allowance		(3,986	)		(3,308	)
Total noncurrent deferred tax assets		25,175			20,989
Noncurrent deferred tax liabilities:
Book over tax basis of certain assets		(5,707	)		(5,959	)
Intangible value		(2,370	)		—
Other		(2,151	)		(2,216	)
Total noncurrent deferred tax liabilities		(10,228	)		(8,175	)
Net total noncurrent deferred tax assets	$	14,947		$	12,814

The tax benefits associated with equity-based compensation increased income taxes payable by $0.8 million and reduced income taxes payable by $1.0 million with a corresponding income tax amount recognized in the accompanying statement of operations for the years ended December 31, 2018 and 2017, respectively, consistent with ASU 2016-09, "Improvements to Employee Share-Based Payment Accounting", which the Company adopted in the first quarter of 2017. The tax benefits associated with equity-based compensation reduced income taxes payable by $1.5 million during 2016 with benefits recorded as increases to stockholders' equity.

A reconciliation of the income tax provision at the statutory income tax rate and the effective tax rate as a percentage of income from continuing operations before income taxes for the years ended December 31, 2018, 2017, and 2016 is as follows:

	2018			2017			2016
Statutory federal rate		21.0	%		35.0	%		35.0	%
Dividends paid deduction		(18.6	)		(31.3	)		(32.5	)
State taxes, net of federal tax benefit		1.0			1.2			1.1
Permanent differences		1.0			0.6			0.3
Charges associated with adoption of tax reform		0.6			2.4			—
Tax benefit of equity-based compensation		0.5			(0.5	)		—
Other items, net		(0.5	)		(0.2	)		(0.3	)
		5.0	%		7.2	%		3.6	%

CoreCivic's effective tax rate was 5.0%, 7.2%, and 3.6% during 2018, 2017, and 2016, respectively. As a REIT, CoreCivic is entitled to a deduction for dividends paid, resulting in a substantial reduction in the amount of federal income tax expense it recognizes. Substantially all of CoreCivic's income tax expense is incurred based on the earnings generated by its TRSs. CoreCivic's overall effective tax rate is estimated based on its current projection of taxable income primarily generated by its TRSs. The Company's consolidated effective tax rate could fluctuate in the future based on changes in estimates of taxable income, the relative amounts of taxable income generated by the TRSs and the REIT, the implementation of additional tax planning strategies, changes in federal or state tax rates or laws affecting tax credits available to the Company, changes in other tax laws, changes in estimates related to uncertain tax positions, or changes in state apportionment factors, as well as changes in the valuation allowance applied to the Company's deferred tax assets that are based primarily on the amount of state net operating losses and tax credits that could expire unused.

CoreCivic had no liabilities for uncertain tax positions as of December 31, 2018 and 2017. CoreCivic recognizes interest and penalties related to unrecognized tax positions in income tax expense. CoreCivic does not currently anticipate that the total amount of unrecognized tax positions will significantly change in the next twelve months.

CoreCivic's U.S. federal income tax returns for tax years 2015 through 2017 remain subject to examination by the IRS. All states in which CoreCivic files income tax returns follow the same statute of limitations as federal, with the exception of the following states whose open tax years include 2014 through 2017: Arizona, California, Colorado, Kentucky, Minnesota, New Jersey, Texas, and Wisconsin.