Former FBI Director James Comey testifies before a Senate Intelligence Committee hearing on Russia's alleged interference in the 2016 U.S. presidential election on Capitol Hill in Washington, U.S., June 8, 2017. REUTERS/Aaron P. Bernstein

By Sarah N. Lynch

WASHINGTON, Dec 1 (Reuters) - The U.S. Justice Department is weighing seeking new indictments against former FBI Director James Comey and New York Attorney General Letitia James, after a federal judge dismissed both cases last week, according to two people familiar with the matter.

The department could seek new charges against Comey and James as soon as this week, though the timing was not yet clear, the people added, speaking anonymously in order to discuss non-public department deliberations.

Representatives for James could not be immediately reached for comment. An attorney for Comey declined to comment.

A federal judge last week dismissed the criminal cases against both Comey and James - two of President Donald Trump's perceived political enemies - after she determined that both indictments were secured by an unlawfully appointed U.S. Attorney in Virginia's Eastern District.

In her ruling, U.S. District Judge Cameron McGowan Currie found that the Trump Justice Department violated the U.S. Constitution's Appointments Clause and federal law by appointing Lindsey Halligan in September as Interim U.S. Attorney.

Halligan's predecessor was forced out of his job after expressing concerns about the evidence in both cases. Halligan presented evidence alone to the grand juries in both criminal cases. Career prosecutors in her office refused to participate.

Currie's ruling left the door open for the Justice Department to try to seek fresh indictments.

Both Comey and James have been longtime targets of Trump's ire. Comey as FBI director oversaw an investigation into alleged ties between Trump's 2016 election campaign and the Russian government, and was fired by Trump in 2017.

James, an elected Democrat, successfully sued Trump and his family real estate company for fraud.

Comey pleaded not guilty to charges of making false statements and obstructing Congress after he was accused of lying and authorizing leaks to the news media.

James pleaded not guilty to charges of bank fraud and lying to a financial institution. Halligan alleged that she filed misleading mortgage documents to secure more favorable loan terms.

Both Comey and James have alleged the prosecutions against them were vindictive, driven by Trump's animus towards them.

It was unclear whether prosecutors could seek to bring a new case against Comey over the same conduct. The five-year statute of limitations on the charges expired on September 30, and Comey's lawyers have already indicated in court filings that they do not believe prosecutors have more time to refile the charges.

(Reporting by Sarah N. Lynch; Editing by David Gregorio)