Imagine Watergate — or even the Clinton impeachment — in a country this divided.

• Americans no longer agree on just about anything, down to the level of who can be trusted to arbitrate truth from fiction or how to differentiate common sense from nonsense, according to a new AP-NORC poll.

Why it matters: Democratic institutions have long functioned on trust that is vanishing before our eyes, with the institutions looking similarly vulnerable.

The big picture, per the poll: 47% of Americans say they struggle to determine whether information is true.

• Democrats and Republicans both struggle with this process, although they turn to very different gatekeepers.
• Nearly two-thirds of Americans say they often come across one-sided information and about six in 10 say they regularly see conflicting reports about the same set of facts from different sources, according to AP.

Between the lines: Democrats are more likely to say they rely on scientists and academics, while Republicans are more likely to trust what they hear from President Trump.

• But majorities have little to no confidence in information they get about the government from social media, the president, members of Congress and businesses, the poll found.

Of note: The poll was conducted Oct. 15–28 of 1,032 adults using a sample drawn from NORC’s probability-based AmeriSpeak panel that's designed to be representative of the U.S. population. The margin of sampling error for all respondents is ±4.2 percentage points.

A police officer stands guard as students wait to reunite with their parents following a shooting at Saugus High School in Santa Clarita, California.

• "At least six people were shot, two fatally," ABC7 News reports.
• Surveillance video "clearly" shows the suspect pulled a semi-automatic handgun out of his backpack in the quad and shot five classmates before shooting himself, according to Capt. Kent Wegener of the sheriff's department.

1. The first televised impeachment hearing drew a sizable audience of about 13 million live viewers, falling short of the 19.5 million for James Comey's testimony and the roughly 20 million for Brett Kavanaugh's hearing. Go deeper.
2. Speaker Nancy Pelosi said yesterday's hearing was "devastating," and that it "corroborated evidence of bribery." Go deeper.
3. Julián Castro has failed to qualify for the November debate stage, just weeks after threatening to drop out over waning fundraising. Go deeper.
4. Global debt surged by $7.5 trillion in the first half of the year, hitting a new record of more than $250 trillion. Go deeper.
5. The restaurant industry is increasingly digital. That's good news for tech, but bad news for restaurateurs. Go deeper.

Scientists are looking for 10,000 pets for the largest-ever study of aging in canines, AP reports.

• The project will collect a pile of pooch data: vet records, DNA samples, gut microbes and information on food and walks.
• The dogs will live at home and follow their usual routine, while owners will complete periodic online surveys and take their dogs to the vet once a year, with the possibility of extra visits for certain tests.

Go deeper: Nominate your dog.