My husband is an officer. He has been for 22 years and I've been around for 20 of those. Its something I'm now used to but it was difficult at first. Working 9-5 mon-fri now would drive me up the wall. I cant be doing with him being at home every single weekend, I'm busy with children's hobbies so him complaining he wants to go and do x,y,z but cant because of the children's activities would drive me bonkers. He works 2 early shifts, 2 afternoon shifts, 2 night shifts then 4 days off.
I love the night shifts (9/10pm- 7am) because I get the bed to myself and I get to do everything I need during the day. He gets up around 4pm and spends time with the children and helps them do homework while I cook dinner etc.
His early shifts (7am - 4pm)are lovely too because he's already been up and used the bathroom when I wake up so I don't have any juggling to do when I get the children up for school. He's home just after the children get home so they see their dad too.
The afternoon shifts I don't like. They start at anytime between 12pm and 4pm, depending on the day of the week and the local staff levels. They finish between 11pm and 4am depending what time they start. These shifts are just wrong as starting at 12pm means they don't get to have lunch before they go and its rare to get a break for dinner during any shift so they often go all day without eating a thing. He always comes home grumpy from afternoon shifts.
Its also nice that he is off during the week sometimes so we get to spend time together and have lunch out which lot of couples cant do as often as we can. Also having a 2 week holiday means he only has to book 6 days off because he can use the 4 rest days before and after his 6 day shifts to take his holiday so they can actually get more holiday than most other professions by working around the shift patterns.
The downside is that if you get invited out at the weekend he may not be home to babysit. My social life is very limited because I just don't know if he will be home or not. I had to cancel a training course I had booked for 5 months because he worked late and didn't get home in time for me to go. That can happen a lot. I never make plans for anything, everything I do is last minute. I've lost a lot of 'friends' because they just don't get why he isn't home to babysit. To them he is doing it on purpose so I cant go out rather than he's still working 
A policeman's wife for me is in effect a single mum who has a husband come home a various times of the week.
My children are very proud of their dad. He received a bravery award recently and he was promoted. My children's faces were amazing when we all went to the ceremony to collect his certificates.
Your (normal) friends will not understand anything you ever have to go through. I am currently having to deal with a lunatic mum at my children's school who is taking it out on me because my husband had to deal with her during his working day.
This can be hard to deal with especially because I don't know what happened to need the police to come out to her and everyone is asking you what she's on about and I cant say anything to them because I don't have a clue about it, they often make up their own stories which can cause more problems.
On occasions 'clients' realise who you are with when out and you can get abuse etc while you are out and about but as long as you don't work where you live (unfortunately my husband just got promoted and moved to our town so im bracing myself for more crap) then life would carry on as before.
Most divorced officers usually marry other police officers and the way the shift system works often means they never see each other. This puts a huge strain on their relationship. Most happily married officers are not married to other officers. The wife does need to understand though that just because the shift should finish at 4pm it doesn't mean that 'clients' are happy to not commit crime during the shift change. A police officer will be home once their paperwork is done and no amount of moaning or tantrums from the wife will change that, I know because I've tried 
But I wouldn't want my husband to do anything else. He loves his job, it would kill him if he were locked in an office all day every day. As everyone else has suggested your husband may need to be a Special Constable or PCSO for 2 years before he can apply anyway so that would give him a good idea as to whether its for him or not.
I love my policeman husband and I wouldn't have it any other way 