The law is broken on both sides. Kids are all grown up now, but it took a LONG time to routinely collect CS from ex--who had an excellent, union income. He took LOA for the sole purpose of going to court to "terminate" his CS obligation for (at that time) four kids under the age of 12.
When he just stopped paying, and I called CS to ask why I hadn't gotten my check, they told me that they'd not gotten it...and that they couldn't investigate till it was X number of days late. I called his employer, only to learn about the LOA.
I have SOME sympathy for the CS workers. They, as was pointed out, are NOT accountants, but social workers. They work long hours, have huge caseloads, and rarely get a kind word from the people they work for; I know I never called them unless something was wrong, and I suspect no one else did, either.
The world of divorce-with-kids seems to be divided into two camps. In one are the parents who try to do right by their kids, no matter that they cannot any longer abide being married to the kids' other parent. Whether they pay or receive CS, all they want is to successfully raise their children to well-balanced adulthood.
In the other camp are the deadbeats, the lying custodial parents--my brother's ex did the same thing, applied for assistance when he WAS paying--and she'd received a large inheritance from her grandfather. Her parents kept it in their name, and she could go on sitting on her fat <censored> without working.
It's all a shame, because the ones who suffer from the parents in that camp are the kids. And the responsible parents, if they are divorced from parents like that, have an extra burden to minimize the negative effects of the rotten ones on their children.
As for cprems' predicament: I suspect that his ex refused to sign the statement, and that, without having the details of the payments at hand in a legally useable form, requires the state and county to issue the summons and complaint in order to get the information. It doesn't matter whether or not they believe him. They need the proof.