The House Ethics Committee says it is looking into actions by Democratic congressman Luis Gutierrez of Illinois.
Gutierrez is in his 11th term representing Chicago and surrounding areas and is a leading advocate of overhauling immigration laws.
A spokesman for Gutierrez said Thursday that the inquiry relates to a long-standing service contract made by Gutierrez over the past decade.
Spokesman Douglas Rivlin says the contract was reviewed and approved by House officials and was submitted for renewal every other year for 10 years. Gutiérrez canceled the contract last year.
Rivlin says Gutierrez has cooperated with the outside organization, the Office of Congressional Ethics, that referred the case to the House ethics panel.
The nature of the inquiry was not disclosed. A report by the ethics committee is due May 5.
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