8. Income Taxes

Income tax provisions for the three months ended March 31, 2021 and 2020 are as follows:


	Three months ended March 31,
	2021		2020
Current:
Federal	$	155,370	$	297,863
State		183,844		96,896
Total current income tax expense		339,214		394,759
Deferred:
Federal		663,202		(131,081)
State		142,157		61,603
Total deferred tax expense (benefit)		805,359		(69,478)
Income tax expense	$	1,144,573	$	325,281

The Company files federal income tax returns in the United States and Canada, and various returns in state and local jurisdictions.

The Company believes it has appropriate support for the income tax positions taken and to be taken on our tax returns and that the accruals for tax liabilities are adequate for all open years based on our assessment of various factors including past experience and interpretations of tax law applied to the facts of each matter. The Company's tax returns are open to audit under the statute of limitations for the years ending December 31, 2017 through December 31, 2020. To the extent we utilize net operating losses generated in earlier years, such earlier years may also be subject to audit.

Our effective tax rate will typically differ from the statutory federal rate primarily as a result of state income taxes and the valuation allowance against the Canadian net operating loss. The effective tax rate for the three months ended March 31, 2021 was higher than the statutory federal rate as a result of the state income taxes and the valuation allowance against the Canadian net operating loss.