Mike Pence has claimed there is “no comparison whatsoever” between his use of a private email account for state business and that of Hillary Clinton.
The US Vice President used the email account during his time as governor of Indiana and Ms Clinton used a private email server while she was Secretary of State.
The former Democratic presidential nominee faced criticism throughout the campaign for the email scandal.
"There's no comparison whatsoever between Hillary Clinton's practise, having a private server that was handling classified information, destroying emails that were requested by the Congress and by officials," Mr Pence told reporters at an event in Wisconsin.
Mr Pence used an AOL email account to discuss sensitive homeland security issues, it has been reported.
The account was apparently hacked last summer, according to the Indianapolis Star.
Mr Pence has claimed he complied with Indiana laws and had an attorney review his private email records.
The FBI assessed Ms Clinton’s emails during the presidential campaign and concluded no criminal charges were necessary,
FBI Director James Comey said the former Secretary State and her colleagues were "careless" with classified information.
A White House spokeswoman said Mr Pence was not subject to federal laws as governor, unlike Ms Clinton.
"There's light years of difference" between the use of private email by Mr Pence and Ms Clinton, White House spokeswoman Sarah Sanders said.
