Normally before a big national holiday, state highway officials would be reminding you of the perils of combining alcohol with heavy machinery, but in the run-up to the Memorial Day Weekend, the message was a little different.

Essentially: Don’t drive like a Jackass star. Back off. Make room. Be courteous. Change lanes if you see a breakdown or a patrol car on the shoulder.

That last one was no coincidence, and came with serious undercurrents.

Related Stories Here's Where Metro Phoenix Cops Will Be Waiting for You During the Holidays

The Arizona Department of Public Safety responded to three bad crashes in 24 hours this week, each a reminder that Arizona has had on the books for years the Move Over Law. You’re supposed to pull over a lane if you see a stopped vehicle or traffic stop in the shoulder.

Apparently, many people don’t comply.

Last year, highway patrol officers ticketed 1,567 violators, up 18 percent from the 1,328 they cited in 2015.

The consequences can be grim, as DPS Director Col. Frank Milstead and crash photos explained as he pointed to display board showing mangled state vehicles.

In one, a patrol officer was citing a truck driver on Interstate 10 when a driver, distracted by his cellphone, “left the roadway and punted that 6,000-pound SUV into the desert,” Milstead said.

In other incident, this time on Interstate 8 and involving another cellphone driver, hit a DPS truck “so incredibly hard, that the motor was then knocked out of the vehicle,” he said.

Arizona Department of Public Safety Director Col. Frank Milstead, left, and Arizona Governor's Office of Highway Safety Director Alberto Gutier Sean Holstege

“The thing that keeps me up at night is the safety of the men and women that work for this agency, and but for the grace of God any of these become fatal collisions and we lose yet another law enforcement officer.”

It’s not an idle concern.

In May 2013, not far from one of the crashes highlighted this week, DPS Officer Timothy Hoffman was on the side of I-8 east of Yuma investigating an injury crash, when a driver smashed into the back of his patrol car. The impact killed Hoffman, the last DPS officer who died this way.

Down the years, DPS trooper and spokesman Kameron Lee said, “Of the 29 DPS officers killed, 10 were killed by passing cars while the officers were either on a traffic stop or investigating a collision.”

It’s not just officers who die. On Sunday, on I-10 near Florence Boulevard, a hit-and-run driver smashed into a car stranded in the emergency lane and killed the driver.

“Off-road collisions continue to be on the rise. Our fatal count is on the rise,” Milstead said.

He noted that already this year, DPS have logged 110 fatal car crashes, of which 99 involved collisions. The fatality count is 10 higher than this time a year ago, which was higher than for 2015, he said.

Memorial Day weekend tends to add to the numbers. Last year, DPS responded to four fatal and 393 nonfatal collisions. In 2015, the highway patrol went to 364 nonfatal collisions but five fatal crashes.

Crashes have a snowball effect. A bad crash can clog a freeway for hours, especially in a pinch point like Interstate 17 north of Phoenix around the Sunset Point rest stop. Milstead said he was proud of bringing the average time to clear an accident down from 38 to 18 minutes in his tenure, but he urged drivers to be more mindful, or they could get stuck in the types of backups that are all too common there on holiday weekends.

The Arizona Department of Transportation will lower speed limits by 10 mph in that area. It starts Friday with northbound traffic and continues Monday in the southbound lanes. ADOT blamed excessive speeds on 40 percent of the crashes on I-17 around Black Canyon City between 2011 and 2015.

ADOT said it will position equipment to move minor wrecks and breakdowns out of the way quickly. DPS will have more patrol cars there to enforce the temporary speed restrictions.

ADOT plans no scheduled highway construction over the holiday weekend.

As usual, DPS will have DUI and aggressive driver task forces out on the highways. The Phoenix Police Department announced a zero-tolerance policy in a stepped-up seatbelt enforcement campaign through June 4.

Some 84 agencies statewide will be working DUI enforcement this weekend, said Alberto Gutier, director of the Arizona Governor’s Office of Highway Safety.

In the Phoenix area, DPS announced DUI warrant roundups and saturation patrols for Friday. In the East Valley DPS will target speed enforcement Saturday. The West Valley DUI task force will concentrate its efforts on Friday and Saturday.

“This is beyond impaired driving. It’s speeding, aggressive driving. Put your seatbelt on. Secure your children properly.” Gutier said.

That was Milstead’s thrust too.

“Human nature is to be good to one and other and to give each people a little more time and a little more space. Somehow we lose that on our roadways,” he said. “This isn’t a law enforcement issue. This is a social issue.”

Here's where law-enforcement officers will be watching you this weekend.

PHOENIX POLICE DEPARTMENT

Saturation Patrol

May 26 and 27 (9 p.m.-4 a.m.)

1610 East Highland Avenue, QT (two vans)

2212 East Bell Road, QT

3443 South Central Avenue

630 East Missouri Avenue, Circle K

2250 East Thomas Road, QT

May 28 and 29 (9 p.m.-4 a.m.)

1610 East Highland Avenue, QT (two vans)

AVONDALE POLICE DEPARTMENT

Sustained Enforcement

May 26, 28, and 29

3200 North Dysart Road, Avondale

GLENDALE POLICE DEPARTMENT

Saturation Patrol

May 28 and 29

Undisclosed locations

PEORIA POLICE DEPARTMENT

Saturation Patrol

May 28 (6 p.m.-4 a.m.)

Undisclosed locations

DPS TASK FORCE

2202 West Encanto Boulevard

CHANDLER PD, DPS METRO EAST,

MESA PD, TEMPE PD

May 26 and 27 (4 p.m.-2 a.m.)

2330 West Rio Salado Parkway, Cubs Stadium, Mesa

ASU PD, CHANLDER PD, DLLC,

DPS METRO EAST, GILBERT PD, MCSO,

MESA PD, PARADISE VALLEY PD,

SALT RIVER PD, SCOTTSDALE PD, TEMPE PD

May 28 and 29 (4 p.m.-2 a.m.)

7601 East McKellips Road, Scottsdale

ASU PD, CHANLDER PD, DLLC,

DPS METRO EAST, GILBERT PD,

SALT RIVER PD, MESA PD,

MSCO, PARADISE VALLEY PD,

SCOTTSDALE PD, TEMPE PD

May 28 (1-6 p.m.)

DUI CHECKPOINT

Power/Redmont

DLLC, MESA PD, DPS METRO EAST,

TEMPE PD

Undisclosed locations

WEST VALLEY DUI TASK FORCE

Saturation Patrol

May 26 (7 p.m.-3 a.m.)

DPS NIGHTWATCH TASKFORCE

2222 West Encanto Boulevard

AVONDALE PD, BUCKEYE PD, DLLC

EL MIRAGE PD, GLENDALE PD,

GOODYEAR PD, MCSO, PEORIA PD,

TOLLESON PD

May 27 (7 p.m.-3 a.m.)

8351 West Cinnabar Avenue, Peoria

AVONDALE PD, BUCKEYE PD, DLLC,

EL MIRAGE PD, DPS NIGHTWATCH,

GLENDALE PD, GOODYEAR PD,

MCSO, PEORIA PD, TOLLESON PD

Undisclosed locations

DPS METRO CENTRAL

DUI Enforcement

Warrant Round Up Detail

May 26

Undisclosed locations

DPS METRO EAST

Speed Enforcement

May 27 (noon-6 p.m.)

Undisclosed locations