This sentence is ingeniously poorly worded.
Which of the following meanings will most Sheeple take it to mean, and which does it actually mean?
1. The U.S. Supreme Court (A) declined on Monday to review a ruling that upheld California's ban on assault weapons and (B) declared there was no constitutional right for individuals to own a gun.
or
2. The U.S. Supreme Court declined on Monday to review a ruling that (A) upheld California's ban on assault weapons and (B) declared there was no constitutional right for individuals to own a gun.
My money says the actual meaning is (2), but most Sheeple will think it says (1). And the criminals at Reuters know this and intend this.
When the court declines to hear a case, it has no affect on the law, it creates no legal precedence, and does not express the Court's opinion on the merits of the case. The Court itself has declared that. However it does allow the ruling of the Court below (in this case the 9th Circuit) to stand, and that ruling is the law in those states within it's jurisdiction. So in California, Arizona, Nevada, Oregon, Washington, Montana and Idaho, there is no individual right to keep and bear arms. AFAIK, only the fifth circuit, covering Texas, Louisiana, and Mississippi, has declared the right protected by the Second Amendment to be one belonging the individuals who make up the group known as "the people". Some say that ruling was mere dicta which does not carry much precedentual weight, and since it was only a 3 judge panel which ruled is not binding on the cicuit as a whole. The 9th circuit Silveira case was also by a 3 judge panel, but previously the entire circuit (en banc) ruled against an individual right.