in 2011, it was exposed that members of congress were allowed to utilize insider trading for personal gain. This became a hot-button issue, and within months, the Stock Act was passed. Basically this meant that the insider trading laws applied to citizens and congress equally.
Recently, (last week) Congress rolled back a big part of this law, specifically the part that required staffers to post disclosures about their financial transactions, so that the public could make sure there was no insider trading going on.
This petition is being created to prevent congress from defrauding the people of the United States, by holding them to the same standards as all US citizens. They should theoretically be held to higher standards, but this is a start, since that likely won't ever happen.