Gabe Rottman, legislative counsel/policy advisor in the ACLU’s Washington Legislative Office, has an interesting breakdown of H.R. 347, the "Federal Restricted Buildings and Grounds Improvement Act of 2011." Signed by the president in mid-March, it expands an existing statute that criminalizes certain activity in and around areas that are restricted by the Secret Service.
Among the more troublesome aspects of the new law:
There are a couple of other details worth noting to understand the full scope of the law. First, the Secret Service does not just protect the president and vice president. Rather, the agency has the responsibility for protecting the president, vice president and their immediate families; former presidents, vice presidents and certain family members; certain foreign dignitaries; major presidential and vice presidential candidates (within 120 days of an election); and other individuals as designated by a presidential executive order. If any of these individuals are temporarily visiting a location, this law kicks in.
Also, lots of attention has been paid to the National Special Security Events, which include things like presidential inaugurations, nominating conventions and even large spectacles like the Super Bowl. The Department of Homeland Security has massive discretion (which in and of itself is a problem) to designate one of these events as an NSSE based on things like the expected number of attendees and the presence of dignitaries.