Answer:

IRS

Answer	Crossword Clue
IRS	April initials
IRS	Spring collection org.
IRS	Tax gr.

IRS	Tax org.
IRS	Tax-collecting org.
IRS	Tax man's boss
IRS	Treasury div.
IRS	Apr. collector
IRS	Govt. tax agency
IRS	Tax agcy.
IRS	The first robbin' of Spring?

IRS	Collection agency: abbr.
IRS	Org. that clashed with the Church of Scientology
IRS	Govt. agency assailed by some for its complex code
IRS	U.S. org. created to help fund the Civil War
IRS	1040 issuer
IRS	Apr. payee
IRS	Treas. Dept. agency
IRS	Org. that takes many forms

IRS	Tax collector
IRS	Collection agcy.
IRS	1040 issuers
IRS	Apr. addressee
IRS	Treasury agcy.
IRS	Unpopular org. in April
IRS	April addressee
IRS	Initials of April

IRS	Yearly collectors
IRS	1040 collectors
IRS	April 15 addressee
IRS	1040 people (abbr.)
IRS	Return addressee?
IRS	Return address? (abbr.)
IRS	Unpopular April letters
IRS	Org. behind audits

IRS	4-15 addressee
IRS	April 15 grp.
IRS	April 15 org.
IRS	Tax grp.
IRS	Taxing agcy.