It was only a few months ago that Hilary Clinton was criticised for using private email servers during her tenure as the Secretary of State. Donald Trump, her opponent at the time, even wanted to prosecute Clinton and have her put behind bars because "having staffers use emails not monitored by the government could be a bad thing," as per Gizmodo's report.
The irony here is that in a report by Newsweek, it was discovered that important Trump staffers are also using private email servers for their email accounts. They named Jared Kushner, Kellyanne Conway, Sean Spicer, and Steven Bannon to be using accounts which run on the Republican National Committee's (RNC) private server. This not uncommon, as former President George W. Bush also had staffers who used RNC emails while working in the White House.
The use of a separate or private email accounts is not an illegal act, and as Newsweek also pointed out, it could also make sense. This is because, not all communications of the staffers would concern the White House. However, they are still required to comply with the Disclosure Requirement for Official Business Conducted Using Electronic Messaging Accounts law.
This law states that employee must copy or forward electronic messages "to an official electronic messaging account of the President, Vice President, or covered employee not later than 20 days after the original creation or transmission of the Presidential or Vice Presidential record." The law went into effect in 2014 and was aimed to address the claims that the Bush administration was using private email accounts in order to avoid the Presidential Records Act of 1978.
Howard Dean, the former chair of the Democratic National Committee, tweeted that "Is the 'crooked Donald' chant appropriate here or do we go right to 'lock him up'?" This is in light of what was mentioned earlier as Donald Trump branded Hilary Clinton as "Crooked Hilary" and wanted to "lock her up." Though, according to the New York Daily, there is no evidence of any illegal activity done by the Trump administration, though it does bring about calls of hypocrisy.