Flags fly in front of the U.S. Capitol in Washington, Tuesday morning, Jan. 1, 2019, as a partial government shutdown stretches into its third week.
Flags fly in front of the U.S. Capitol in Washington, Tuesday morning, Jan. 1, 2019, as a partial government shutdown stretches into its third week.

When the Democrats took control of the U.S. House of Representatives earlier this month, the new committee chairs said they would use their role of oversight to begin investigating the controversies and scandals regarding President Donald Trump's businesses, campaign and administration.

 A Look at the History and Importance of Congress' Power to Investigate

A Look at Upcoming Investigations by House Committees

Russia inquiry

*At least four House committees plan to look into aspects of the Russian election interference investigation — Intelligence, Financial Services, Foreign Affairs, and Judiciary. However, none plan to reopen a full-scale investigation, since Democratic officials say special counsel Robert Mueller's probe is already doing that. House Judiciary Chairman Jerrold Nadler says he will wait for Mueller to conclude his investigation before considering any possible impeachment inquiry.

The lines of questioning by the committees reflect their particular purview. For example, the Foreign Affairs Committee will look into what Trump said to Russian President Vladimir Putin during their private meeting last summer in Helsinki, Finland, while the Financial Services Committee plans to seek financial records relating to hundreds of millions of dollars in loans from Deutsche Bank to the Trump Organization.

FILE - Rep. Richard Neal, D-Mass., ranking member
FILE - Rep. Richard Neal, D-Mass., ranking member of the House Ways and Means Committee, speaks on Capitol Hill in Washington, May 24, 2017.

?Trump's taxes

* Ways and Means Committee Chairman Richard Neal says he wants to try to build a public case for why Trump's tax returns should become public before he makes any formal request for the returns to be released. He says he will hold hearings on the matter and will propose legislation that would require all presidents and candidates for the office to make their returns public. If Neal does request the tax returns from the Treasury Department, he has the authority under the tax code to be granted them as chairman of a House committee, however it is not clear if the Trump administration would challenge the matter.

Immigration policies

* Top Democrats have made clear they want to investigate the Trump administration's immigration policies, with several committees planning to look into the matter of family separations and detentions at the border.

* The House Judiciary Committee plans to investigate the recent deaths of two migrant children held in detention — Jakelin Caal, 7, and Felipe Gomez Alonzo, 8. Three committees have ordered U.S. Customs and Border Protection to preserve evidence related to their deaths.

A man looks at a TV screen showing North Korean le
FILE - A man looks at a TV screen showing North Korean leader Kim Jong Un, left, and U.S. President Donald Trump shaking hands before their meeting in Singapore, in Tokyo, June 12, 2018.

?Foreign issues

* In addition to Russia, the Foreign Affairs Committee plans to investigate issues involving several countries, including North Korea, Saudi Arabia and Syria. The committee plans to look at Trump's relationship with North Korean leader Kim Jong Un as well as his family's close ties with the Saudi crown prince.

* It also wants answers to why Trump abruptly announced in December the withdrawal of 2,000 U.S. forces from Syria, which led to the resignation of Defense Secretary James Mattis.

* The new chair of the Foreign Affairs Committee, Eliot Engel, says he plans to create an entire subcommittee devoted to investigating Trump.

Domestic issues

* The House Judiciary Committee wants to look into Trump's decision to fire former Attorney General Jeff Sessions and what his acting Attorney General Matthew Whitaker knew about the decision.

* It also wants to investigate Trump's involvement in payments before his 2016 election to two women who claim to have had affairs with Trump, a possible campaign finance violation.

* The Oversight and Reform committee will look at a host of other domestic issues, including the use by Trump daughter Ivanka Trump of a private email account for government business, the Trump administration's response to hurricanes Irma and Maria, and some Trump Cabinet officials' use of government jets for personal travels.