Megan Brenan:

Americans’ rating of the Secret Service’s job performance has deteriorated sharply to a new low in Gallup’s 10-year trend. The latest poll was completed almost entirely before the Sept. 15 apparent assassination attempt on Donald Trump, the second in nine weeks. About one in three U.S. adults now rate the Secret Service’s performance as “excellent” (8%) or “good” (24%), while 25% say it is “only fair” and 36% “poor.”

The Sept. 3-15 poll was conducted as various government entities continue to investigate the Secret Service’s reported lapses in the July 13 assassination attempt on Trump in Butler, Pennsylvania. Amid these highly publicized investigations, the percentage of Americans rating the Secret Service as excellent or good plunged 23 percentage points, while the share of those rating it as poor rose by the same margin.

The current findings are in marked contrast with four of the five previous readings over the past decade. The Secret Service — the federal law enforcement agency charged with keeping political leaders safe — has typically enjoyed broadly positive ratings from the public, with majorities offering an excellent or good assessment of its performance.

Since 2014, an average of 53% of Americans have rated the Secret Service positively. Yet, this year is not the first time the agency has failed to receive a majority-level excellent or good rating. The initial 43% positive rating in 2014 followed several security lapses, including one in which an intruder jumped a fence and entered the White House.