White House moving forward with 19 executive orders on gun control

How can you use executive orders to institute the same rules that previously required legislation?  Wouldn't Bill Clinton have liked to implement the 1994 assault weapon ban by executive order?  How can you get around the existing legislative prohibitions on gun research by the government health organizations by an executive order?  From Politico:

Later this week, Obama will formally announce his proposals to reduce gun violence, which are expected to include renewal of the assault weapons ban, universal background checks and prohibition of high-capacity magazine clips. But Biden, who has been leading Obama’s task force on the response, spent two hours briefing a small group of sympathetic House Democrats on the road ahead in the latest White House outreach to invested groups. 

The focus on executive orders is the result of the White House and other Democrats acknowledging the political difficulty of enacting any new gun legislation, a topic Biden did not address in Monday’s meeting. 

The executive actions could include giving the Centers for Disease Control and Prevention authority to conduct national research on guns, more aggressive enforcement of existing gun laws and pushing for wider sharing of existing gun databases among federal and state agencies, members of Congress in the meeting said. . . .